DOE/E R-0401

Summaries of FY 1988

Engineering Research

1988

U.S. Department of Energy

Office of Energy Research

Office of Basic Energy Sciences

Division of Engineering and Geosciences
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DOE/ER-0401

Summaries of FY 1988

Engineering Research

1988

U.S. Department of Energy

Office of Energy Research

Office of Basic Energy Sciences

Division of Engineering and Geosciences

Washington, D.C. 20545
FOREWORD

This report documents the BES Engineering Research program for fiscal year

1988; it provides a summary for each of the program projects in addition to a brief

program overview. The report is intended to provide staff of Congressional committees, other executive departments, and other DOE offices with substantive

program information so as to facilitate governmental overview and coordination

of Federal research programs. Of equal importance, its availability facilitates

communication of program information to interested research engineers and

scientists. The organizational chart for the DOE Office of Energy Research

(OER) on the next page delineates the six Divisions within the OER Office of

Basic Energy Sciences (BES). Each BES Division administers basic, mission

oriented research programs in the area indicated by its title. The BES Engineering Research program is one such program; it is administered by the Engineering

and Geosciences Division of BES. Dr. Oscar P. Manley is technical manager of

the Engineering Research program; inquiries concerning the program may be addressed to him, in writing or by phone at (301) 353-5822.

In preparing this report we asked the principal investigators to submit summaries for their projects that were specifically applicable to fiscal year 1988. The

summaries received have been edited as necessary, but the press for timely publication made it impractical to have the investigators review and approve the summaries prior to publication. For more information about a given project, it is

suggested that the investigators be contacted directly.
Engineering Research Program

within DOE

Secretary of Energy

Deputy Secretary

Under Secretary

Assistant Secretaries Office of Energy Research * Federal Energy

· Nuclear Energy Regulatory Commission

· Conservation and Renewable * Economic Regulatory

· Fossil Commission

· Defense * Energy Information

· Environmental Administration

· International Affairs etc.

II I

· Program Analysis Basic Enery Sciences * Management

· Magnetic Fusion * Special Programs

· High Energy and Nuclear Physics * Scientific Computing

· Health and environmental Research

· Field Operations

I !

* Material Sciences Division Engineering and * Advanced Energy Projects

* Chemical Sciences Division Geosciences Division * Biological Energy

Research

* Carbon Dioxide

Research

Engineering

Research Program
INTRODUCTION

The individual project summaries follow the program overview. The summaries

are ordered alphabetically by name of institution and so the table of contents lists

all of the institutions at which projects were sponsored in fiscal year 1988.

The projects are numbered sequentially for individual identification in the indexes. Each project entry begins with a centered, institutional- departmental

heading. The project number precedes the capitalized project title. The names

of the investigators are listed immediately below the title. The funding level for

fiscal year 1988 appears to the right of title; it is followed by the budget activity

number (e.g., 01A). These numbers categorize the projects for budgetary purposes and the categories are described in the budget number index. The year in

which the project began and the anticipated duration in years are indicated

respectively by the first two and last digits of the sequence directly below the

budget activity number (e.g., 88-). The summary description of the project completes the entry.
PROGRAM REVIEW

BES ENGINEERING RESEARCH

The BES Engineering Research program is one ticipated in the workshops. In addition to the parof the component research programs which col- ticipants in the workshops, staff representatives

lectively constitute the DOE Basic Energy Scien- from the DOE technology programs and other

ces program. The DOE Basic Energy Sciences leadingU.S. energy engineering experts made sigprogram supports energy related research in the nificant contributions to the setting of program

physical and biological sciences, and in engineer- priorities. There resulted from this process a

ing. The chief purpose of the DOE Basic Energy strong confirmation of the need for a long range,

Sciences program is to provide the fundamental fundamental engineering research program with

scientific base on which identification and two major goals. The broad goals that were estabdevelopment of future, national energy options lished by this process for the BES Engineering Rewill depend. The major product of the program search program are:

becomes part of the body of data and knowledge 1) To extend the body of knowledge underlying

upon which the applied energy technologies are current engineering practice so as to create new

founded; the product is knowledge relevant to options for enhancing energy savings and producenergy exploration, production, conversion and tion, for prolonging useful equipment life, and for

use. reducing costs without degradation of industrial

The BES Engineering Research program was production and performance quality; and

started 1979 to help resolve the numerous serious 2) To broaden the technical and conceptual

engineering issues arising from efforts to meet base for solving future engineering problems in

U.S. energy needs. The program supports fun- the energy technologies.

damental research on broad, generic topics in In this process, it was further established that to

energy related engineering topics not as narrowly achieve these goals, the BES Engineering Rcscoped as those addressed by the shorter term en- search program should address the following

gineering research projects sponsored by the topics identified as essential to the progress of

various DOE technology programs. Special em- many energy technologies:

phasis is placed on projects which, if successfully 1) Advanced Industrial Technology: improvcconcluded, will benefit more than one energy ment of energy conversion and utilization, opentechnology. During the first year several ing new technological possibilities, and

workshops were sponsored for the purpose of improvement of energy systems.

identifying energy related engineering research 2) Fluid Dynamics and Thermal Processes:

needs and initial priorities. Representatives from broadening of understanding of heat transfer in

industry, academic institutions, national nonsteady flows, methodology for reducing vibralaboratories, and leading members of professional tions and noise in heat exchangers, and engineerorganizations (Engineering Societies Commis- ing aspects of combustion.

sion on Energy, American Society of Mechanical 3) Solid Mechanics: continuum mechanics and

Engineers, Society of Automotive Engineers, and crack propagation in structures.

Joint Automation and Control Committee) par-
4) Dynamics and Control of Processes and Sys- All such activities will be supported and adtems: development and use of information ministered directly by the Engineering Research

describing system behavior (system models), per- Program, but some coordination of efforts with

formance criteria, and theories of control op- the ORNL program may prove useful. The retimization to achieve the best possible system search opportunities in this area of interest to the

performance subject to known constraints. DOE Engineering Research Program have been

A Scoping Workshop held in December, 1985 identified in a workshop held in November, 1983.

confirmed the continued needs for research in Proceeding of the workshop entitled "Research

these topical areas. Because of budgetary limita- Needs in Intelligent Machines" are available from

tions, the implemented BES Engineering Re- the Center for Engineering Advanced Systems

search program is somewhat less broad than the Research, Oak Ridge National Lab, Post Office

program envisioned above. At present, equal em- Box X, Oak Ridge, TN, 37830.

phasis is being placed on three carefully selected, Secondly in FY 1985 there has started a colhigh priority research areas; namely, laborative research effort between MIT and Idaho

1) Mechanical Sciences including tribology National Engineering Lab. At present, the col-

(basic nature of friction reduction phenomena), laboration is in four distinct areas: Plasma

heat transfer, and solid mechanics (continuum Process Engineering, Automated Welding, Fracmechanics and crack propagation). ture Mechanics, and Advanced Engineering

2) System Sciences including process control Methods and Analysis.

and instrumentation. Colateral, high quality research efforts at other

3) Engineering Analysis including nonlinear institutions are supported by the Engineering Redynamics, data bases for thermophysical proper- search program.

ties of fluids, and modeling of combustion proces- In the expectation of a future modest growth of

ses for engineering application. this Program, two International Workshops on

These areas contain the most critical elements of Two Phase Flow Fundamentals were held one in

the four topics enumerated above; as such they are September 1985 and the other in March 1987. The

of importance to energy technologies both in the meetings were used to identify basic research

short and long term, and therefore of immediate needs in the field of two phase flow and heat transprogrammatic interest. It should be noted that fer; summary reports of the workshops are availother areas of basic research important to en- able from the Program Office. The full

gineering are monitored elsewhere in BES. For proceedings of the first workshop have been

instance, separation sciences and research on published as a volume in the series "Advances in

thermophysical properties are among the respon- Heat and Mass Transfer" (Hemisphere Publishsibilities of the Chemical Sciences Division, while ing Company), while those of the second are in

microscopic aspects of fracture mechanics are in preparation for publication in the same series.

the domain of the Material Sciences Division. As Two additional workshops were held during

resources permit, other high priority areas are 1988. The first dealt with possible research opbeing added to the Engineering Research portunities in the field of novel devices using the

program. Thus as a result of some growth in the new high temperature superconductors. The

program budget an important development has second addressed research needs for bioprocesstaken place in the Engineering Research ing of fuels and related wastes. Reports of both

Program: two major concentrations of research workshops are in preparation.

were initiated. First, a new program was or- It should be mentioned too, that some very

ganized at Oak Ridge National Lab dealing with limited support is available for research on large

intelligent machines in unstructured environment. scale systems. A report of a Workshop on Needs,

It is expected that some resources will be available Opportunities, and Options in this field is availfor coordinated, more narrowly focussed related, able from Professor G. L. Thompson, Graduate

high quality research at universities and other re- School of Industrial Administration, Carnegiesearch centers. Mellon University, Pittsburgh, PA, 15213.
Research projects sponsored by the BES En- project has a reasonable chance of being funded.

gineering Research program are currently under- The primary considerations for possible support

way at universities, private sector laboratories, are the technical quality of the proposal and the

and DOE national laboratories. In fiscal year professional standing of the principal inves1988 the program operating funds available tigators and staff. An effort is made to attract first

amounted to about $14.5 million. The distribution rate, younger research engineers and energy

of these funds among various institutions and by oriented applied scientists. A high technical

topical areas is illustrated on the next page. caliber of research is maintained by requiring that

Project funding levels are mostly in the range of the projects supported have potential for a sig-

$50,000 to $150,000 per year. Typical duration of nificant contribution to energyrelated engineering

a project is three to four years, with some projects science, or for an initial contribution to a new

expected to last as long as ten years or more. The energy relevant technology. Sponsored projects

BES Engineering Research projects stem almost are selected primarily for their relevance to DOE

without exception from proposals for competitive mission requirements; the contribution to energy

grants. Proposals which anticipate definite results related higher education is an important but

in less than two years are usually referred to the secondary consideration. Thus projects sponappropriate DOE technology program for con- sored at universities are essentially limited to adsideration. All those interested in submitting a vanced studies both theoretical and experimental

proposal are encouraged to discuss their ideas usually performed by faculty members, staff rewith the technical program manager prior to sub- search scientists, and doctoral candidates.

mission of a formal proposal. Such discussion

helps to establish whether or not a potential
ENGINEERING RESEARCH PROGRAM

FY '88 BUDGET ($000's)

BY INSTITUTIONAL TYPE

UNIVERSITIES

I .$8716 \

LABORATORIES (94 PROJECTS)

30%

$4338

(20 PROJECTS)

OTHER

10%

$1383

(11 PROJECTS)

ENGINEERING RESEARCH PROGRAM

FY '88 BUDGET

BY TECHNICAL AREAS

($000 s) % NUMBER OF PROJECTS

MECHANICAL SCIENCES 4283 30 46

SYSTEMS SCIENCES 4753 33 24

ENGINEERING ANALYSIS 5400 37 54
Table of Contents

AMES LABORATORY .......................... 1

ARGONNE NATIONAL LABORATORY ............... 1

ARIZONA STATE UNIVERSITY .................... 2

BOSTON UNIVERSITY ......................... 2

BROWN UNIVERSITY .......................... 3

UNIVERSITY OF CALIFORNIA, BERKELEY ............ 4

UNIVERSITY OF CALIFORNIA, DAVIS ............... 5

UNIVERSITY OF CALIFORNIA, LOS ANGELES ......... 6

UNIVERSITY OF CALIFORNIA, SAN DIEGO ........... 7

UNIVERSITY OF CALIFORNIA, SANTA BARBARA ....... 9

CARNEGIE MELLON UNIVERSITY ................ 10

UNIVERSITY OF CHICAGO ..................... 11

CLARKSON UNIVERSITY ...................... 11

COLORADO SCHOOL OF MINES ................. 12

UNIVERSITY OF CONNECTICUT .................. 12

CORNELL UNIVERSITY ....................... 13

DARTMOUTH COLLEGE ....................... 13

ENGINEERING SCIENCE SOFTWARE, INC ........... 14

G. A. TECHNOLOGIES, INC. ..................... 14

UNIVERSITY OF HOUSTON ..................... 14

IDAHO NATIONAL ENGINEERING LABORATORY ...... 15

UNIVERSITY OF ILLINOIS ...................... 18

UNIVERSITY OF ILLINOIS AT CHICAGO ............ 19

ILLINOIS INSTITUTE OF TECHNOLOGY ............. 20

JET PROPULSION LABORATORY ................. 20

LAWRENCE BERKELEY LABORATORY ............. 21

LOS ALAMOS NATIONAL LABORATORY ............ 22

UNIVERSITY OF MARYLAND .................... 22

UNIVERSITY OF MASSACHUSETTS ................ 24

MASSACHUSETTS INSTITUTE OF TECHNOLOGY ...... 25

UNIVERSITY OF MINNESOTA ................... 31

NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY32

THE CITY UNIVERSITY OF NEW YORK The City College . . . 33

NORTH CAROLINA STATE UNIVERSITY ............ 35

NORTHWESTERN UNIVERSITY .................. 35

UNIVERSITY OF NOTRE DAME ................ 37

OAK RIDGE NATIONAL LABORATORY ............. 37

PHYSICAL SCIENCES INC ...................... 37

Engineering Research 1988
PURDUE UNIVERSITY ........................ 38

RENSSELAER POLYTECHNIC INSTITUTE ............ 39

THE ROCKEFELLER UNIVERSITY ................ 40

SANDIA NATIONAL LABORATORIES .............. 40

SCIENCE APPLICATIONS INTERNATIONAL CORPORATION 41

SOLAR ENERGY RESEARCH INSTITUTE ............ 41

STANFORD UNIVERSITY ....................... 42

STEVENS INSTITUTE OF TECHNOLOGY ............ 45

UNIVERSITY OF TEXAS AT AUSTIN ............... 45

TUFTS UNIVERSITY .......................... 47

UNITED TECHNOLOGIES RESEARCH CENTER ........ 47

WASHINGTON STATE UNIVERSITY ............... 47

WESTINGHOUSE R&D CENTER .................. 48

UNIVERSITY OFWISCONSIN .................... 48

Engineering Research 1988
AMES LABORATORY ARGONNE NATIONAL LABORATORY

Institute for Physical Research $250,000 Materials & Components Technology Div. $125,000

and Technology 03-B Argonne, IL 60439 01-C

Ames, IA 50011-3020 87-3 86-3

1. New Ultrasonic Imaging and Measurement 2. TheoreticaVExperimental Study of Stability

Techniques for NDE Control.

D.O. Thompson, D.K Hsu TM. Mulcahy, E.L Reiss

(Northwestern University), S.P.

The objective of this project is to develop new Vanka

knowledge and techniques for the nondestructive

detection and characterization of flaws and non- Theoretical and experimental studies are aimed at endestructive measurements of material properties that hancing the understanding of stability phenomena inareofimportanceinobtainingreliabilityandintegrity volving fluids, solids, and their coupling. The

in materials and structures. In order to achieve this objective is to develop methods of controlling, delaygoal, use is made of new and unique multiviewing in- ing, and/or avoiding instability in engineering comstrumentation that was previously developed in this ponents. Currently fluidelastic instabilities caused by

work and which uses quantitative inverse elastic wave flow leaking between closely spaced bodies are being

scattering theories in the interpretation of results. investigated.

Three major thrusts are being pursued: p experimentally observed To interpret and present the experimentally observed

1) New techniques for ultrasonic computer fluid-structure interaction at the slip-joint region of

tomographic imaging (reconstruction) are being ex- telescoping tubes conveying fluids, a mathematical

plored that utilize elastic wave scattering models and model of the unsteady, one-dimensional flow in a narthe new multiviewing instrumentation. This could be row, finite length channel, which includes a piecewise

an important innovation in that images so obtained linear variation in channel width and several sharpare expected to be free of distortions due to the ef- edged constrictions, has been solved for harmonic

fects of material anisotropy and complex sample sur- perturbations in the channel width. Model problem

faces-encountered in some current imaging parameter variations are being investigated to identechniques. tify spatial distributions of flow resistance which

produce negative flow-damping and dynamic in- 2) Novel techniques are being explored that can be produce negative flow-damping and dynamic inused to produce ultrasonic transducers with special- tbtes r the fndmena not explainable using tubes. Observed phenomena not explainable using ized features to significantly improve flaw and . one-dimensional flow models will be investigated material property detection and characterization. o f m w . .~. .' . e, ,~. .~. using computational fluid mechanics techniques. One such technique is now in place for the development of practical Gaussian beam transducers. This Another model problem, consisting of two different,

transducer has many benefits including no sidelobes infinitely long, uniform, and parallel flow channels

and no rapid fluctuations in the near field. The tech- that interact through a common wall, has been formunique is being extended with the objective of discover- lated to study linear and nonlinear responses and to

ing ways to fabricate other acoustic transducers that develop mathematical techniques. In particular, spashow essentially diffractionless features over a sub- tially periodic bifurcation and secondary bifurcation

stantial propagation distance. solutions for the three channel walls, modeled using

3) Studies have been initiated using broadband nonlinear von Karman plate theory, are being inves- 3) Studies have been initiated using broadband , . , , . '. * i * n .., , .. . , , 6 . ......... tigated for steady, one-dimensional viscous flow unipolar pulse techniques developed earlier on this gated for steady, one-dimensional viscous flow project,, bmodeled to, charcterz' . by Darcy's law. Also sought is justification project to characterize "fuzzy boundaries in .project to chateri ze "fuzzy" boundaries i.n for the use of Darcy's law as an approximation to the materials. This measurement depends largely upon Navier Stokes equations. Navier Stokes equations. being able to detect acoustic impedance changes over

a small but finite spatial dimension, a condition that

is nearly impossible to observe using conventional

ultrasonics. The detection and characterization of

"fuzzy" boundaries is of importance in the control of

various materials processes and in the study of twophase systems.

Engineering Research 1 1988
ARGONNE NATIONAL LABORATORY A theoretical model for predicting the combustion

Materials and Components $125,000 and heat transfer characteristics in planar porous

Technology Division 01-A media as a function of the relevant factors is being

Argonne, IL 60439 84.3 developed. The model includes finite-rate reaction

kinetics and the equation of transfer for describing

radiative heat transfer in porous media. A heat trans3. Bounds on Dynamic Plastic Deformation fer analysis has been performed indicating the inG.K. Youngdahl fluence of the optical and thermal properties of the

porous media and the location of the heat generation Analytical studies are being performed to develop zone of the radiant output. The effect of radiative

load correlation parameters which can be used in ap- heat transfer on flame structure and burning velocity

proximating or bounding the dynamic plastic defor- have been revealed in some preliminary calculations

mation of structures. In many applications where the using a single-step reaction model

load is transmitted to the structure through a fluid,

details of the load history and spatial distribution sig- Experimental measurements are being conducted to

nificantly affect the final plastic deformation. The ob- validate the theoretical model. A laboratory-scale

jective of the program is to devise load correlation burner is being used to obtain flame speed, product

parameters based on various weighted integrals of the species concentration and temperature profiles, and

time-space load distributions which can be used to energy output data under various operating condicharacterize the effects of the load without resorting ti

ons for comparison to theoretical predictions. In

to detailed numerical analysis. These load correla- addition, the limits for free-flame, stable interstitial

tion parameters have three important uses: to per- combustion, and flashback are being determined.

form design and safety analyses of structures over a The findings will be useful for applying the relatively

wide range of design variables and loadings; to unexploited technology of porous radiant burners to

validate computer programs which have a nonlinear industrial heating systems, yielding potentially large dynamic plasticity capability, and to correlate ex- savings in energy consumption and operating costs for

perimental simulations with actual or predicted the industrial sector. The results will also provide a

events. The dynamic plastic deformation of some scientific basis for understanding combustion and

basic structural configurations will be analyzed for heat transfer in other energy technologies including

loadings which vary both in magnitude and region of catalytic combustors and combustion in packed beds

application with time. Load correlation parameters and geological systems.

will be hypothesized and their usefulness in predicting final plastic deformation will be determined. The

analyses will be based initially on a rigid, perfectly

plastic material model and small deformation BOSTON UNIVERSITY

response, but will be extended to include strain har- Department of Chemistry $68,000

dening, an initial elastic response period, and large Boston, MA 02215 06-C

deformation interactions. 863

5. Diffusion, Fluid Flow, and Sound

ARIZONA STATE UNIVERSITY Propagation in Disordered Media

Department of Mechanical $60,000 T. Keyes

and Aerospace Engineering 06-B

Tempe, AZ 85287-6106 87-3 The goal of this project is a unified theoretical attack

on transport processes-prime examples being those

mentioned in the project title-in highly disordered, or

4. Combustions and Heat Transfer in Porous inhomogeneous, materials. We are especially interMedia ested in materials with percolation thresholds, at

RE. Peck, T. W. Tong which the disorder is so large that transport is blocked altogether, and in those with aspects of fractal

A study of combustion and heat transfer of premixed, structure. Another topic is the dynamics of the forgaseous fuel-air mixtures in inert porous media is un- mation of disordered materials via phase separation.

derway. The objective is to generate fundamental in- Since the theoretical methods needed to treat one

formation about flame propagation and heat release problem can usually be applied to others, the

behavior in porous materials. presence of large disorder is more important than the

Engineering Research 2 1988
particular process to be studied. In the past year, we BROWN UNIVERSITY

have obtained results in several areas. Division of Engineering $120,000

Porous materials may be modeled, with considerable Providence, RI 02912 06-C

flexibility, by appropriately placed, specularly reflect- 843

ing spheres. For the case of randomly placed spheres

which are allowed to overlap, free space is partitioned 6. Two Studies of Nonlinear Processes in

into islands above a critical density and transport must Irreversible Thermodynamics

cease. In attempt to study gas flow in porous .Kestin

materials, we have considered the motion of a tagged

point particle in this model solid with the "repeated The project studies two potentially productive lines of

ring" kinetic equation and found a critical density and, research into two well-defined problems, both linked

in general, good agreement with computer simula- inthat they fall into the broad field of irreversible thertions. When the spheres are given some nontrivial modynamics.

structure, e.g., are forbidden from overlapping, the

equation becomes very difficult to solve. In the past The first task studies a mathematical formalism for

year, we have developed the method of "stochastic the qualitative analysis of the geometric-topological

simulation" as a new tool for solving the equation. We structure of all trajectories (solutions) of a mathededuce from the kinetic equations the rules for a matical model of two-phase flow conducted in a phase

simulation that solves the equation exactly. We have space formed with the thermodynamics state varialso augmented variational methods previously ables, the velocities of the two-fluid phases and the

derived with a new approximation for the "boundary space variable.

layer" around the tagged particle in a theory that The most important result of the analysis is a complete

should work for partially overlapping spheres. resolution of the problem of choking. The theory

On another front, we developed the method of "initial leads to a classification of points in phase space into:

stage renormalization" to allow renormalization (a) regular points; (b) turning points; and (c) singular

studies of unstable states. This was applied to the for- points. Points (a) are not descriptive of choking, and

mation of two-phase systems via spinodal decomposi- through them there passes one and the only one

tion. The theory should allow a study of how the trajectory. Points (b) describe choking at the end of

spatial structure of the initial state affects the phase the channel, and points (c) describe choking inside

separation. the channel. The analysis is applicable to a wide class

of mathematical models of two-phase flow now

Finally, we have continued our work on light scatter- employed in industry and makes use of the powerful

ing from disordered materials. We showed how, with tools of the mathematical discipline of dynamical sysvery high angular resolution, it is possible to observe ters.

the statistics, not just the mean, of the scattered intensity. We identified a "critical angle" dividing two The present task is to examine the qualitative effects

statistical regimes. From measurement of the critical of nonequilibrium on the general flow characteristics

angel, it is possible to measure the density of in- and on critical flow. In particular, a combined

homogenieties in the sample; this is a completely new numerical and analytic study has re-interpretcd the

type of measurement. The method is now being ap- well-known Moby Dick experiments suggesting at

plied to characterization of glass ceramics. this stage provisionally, that critical flow was not

reached in the throat but at the end of the experimen- In related work, we gave a version of fractal geometry tal channel. This possibility may lead to a revision of

which allows the discussion of differences between our views on choking in two-phase flow.

fractal structures with identical fractal dimensions,

and we used the scheme to calculate light scattering The second task seeks to apply the methods of classiintensities from disordered materials modeled as cal ("conservative") thermodynamics to self-consisfractals. tent formulations of constitutive laws descriptive of

inelastic deformations, damage and fracture, with

,special emphasis on plastic deformation. The identification of the internal variables and their associated

intensive affinities is essential for the calculation of

entropy and for the derivation of explicity formulae

which are descriptive of the local rate of entropy

production in each system.

Engineering Research 3 1988
Good success has been achieved with the formulation fluence on local heat transfer may be less significant

of an elementary theory of fracture in cooperation than the turbulent transfer of heat.

with Professor G. Hermann of Stanford University whih Profesr l . erann of Stanor Uniersity The experimental results of this study will be used to

develop a phenomenological model for the

predominant heat transfer mechanisms in turbulent

flow containing swirl. We expect that a turbulent heat

flux model incorporating both gradient-type diffusion

UNIVERSITY OF CALIFORNIA, (caused by the small-scale turbulence) and bulk conBERKELEY vective transport (induced by the large-scale motion)

DepartmntofMec l En g n 60 may be appropriate for these flows. Computational Department of Mechanical Engineering $65000 predictions of the local Stanton numbers will be made Berkeley, CA 94720 01-B Berkeley, 0B CA utilizing 94720 the heat transport model 87-3

7. The Turbulent Transport of Heat Within a UNIVERSITY OF CALIFORNIA,

Longitudinal Vortex/Boundary Layer BERKELEY

Interaction Department of Mechanical Engineering $ 0 P.A. Eibeck Berkeley, CA 94720 06-C

86-2 The physical processes that govern the transport of

heat in turbulent, three-dimensional flows are not well

understood, yet successful predictions of local con- 8. Investigation of Secondary Motions and

vective heat transfer in most practical engineering Transition to Turbulence in Buoyancy-Driven

flows require this information. Scalar transport in Enclosure Flows with Streamline Curvature

these complex flows is controlled by turbulent dif- JA.C. Humphrey

fusion coupled with advection introduced by organized flow motions. The objective of this research A study is underway to clarify the role of secondary

program is to experimentally and computationally motions and transition to turbulence in buoyancy

study the contribution of both mechanisms to the ther- driven enclosure flows. The primary flow of interest

mal transport in a boundary layer containing lon- is determined by the boundary conditions imposed

gitudinal swirl. along the side walls of the enclosure. The conditions

induce the unsteady collision of two buoyancy driven, Three different flows are being studied; the single vor- induce the unsteady collision of two buoyancy driv

tex embedded in a turbulent boundary layer, the trail- opposed vercal boundary layers

ing legs of a horseshoe vortex, and flow downstream Experiments are underway with the objective to map

of a spanwise row of obstacles. The single vortex is 2 - and 3-D unsteady flow structures as a function of

the simplest of these flows, such that detailed thermal the Rayleigh number. The measurements consist of

transport measurements will isolate the influence of simultaneous determinations of temperature at two

swirl from other flow complexities. points as a function of the distance between them and

The ..trailing legs of a horseshoe vortex, locd time. Autocorrelations, power spectra, length and The trailing legs of a horseshoe vortex, located downstream of a stream-lined obstacle, have been ob- time scales are being derived from the time histories.

These observations are being interpreted with cor- served close to the wall by our mean velocity measure- esonding fow visualization images. The results This will have flow responding flow visualization images. The results ments. This flow will have thermal transport ments. This flow will have thermal transport show that when the temperature difference of the influenced by both the swirl of the vortices and the at crre ndin t a aei nu e of wake effects. plates is 2oC, corresponding to a Rayleigh number of ~~wax~kee e~~ffectl~s. 109, the persisting 3-D vortices align themselves in

The flow downstream of a spanwise row of obstacles the spanwise direction. The cross correlation of

presents the most complex flow configuration. Each temperature measurements shows that there are wave

obstacle will be rectangular with a height roughly propagations in the spanwise direction.

equal to the boundary layer thickness. In addition to T r The results of this work are expected to contribute horseshoe-type vortices that will be generated at the T o t , t horseshoe-type vortices that will be generated at the directly to the basic understanding of transition to tur- leading edge, separation of the flow over the elements bulence and turbulent flow, and the ability to model and reattachment downstream will lead to very large these flows mathematically. In this regard, a direct

levels of turbulent mixing. The coherent vortical mo- numerical simulation has been performed that tions may still remain present, but their convective in- umerical simulation has been performed th

Engineering Research 4 1988
models a simplified aspect of the experimental flow UNIVERSITY OF CALIFORNIA,

configuration with shear super imposed. The calcula- BERKELEY

tions confirm the experimental evidence pointing to a Departmet of Mechanical Engineering $81,000

dependence of the 3-D instability wavelength on the Berkeley, CA 94720 01-B

Richardson number. 873

UNIVERSITY OF CALIFORNIA, 10. Radiation In Particulate Systems

BERKELEY CL ten

Department of Electrical Engineering $97,000 This study investigates,.through a combined analytiand Computer Sciences 06-C cal and experimental program, inter-particle interacBerkeley, CA 94720 87-3 tions in the radiative scattering absorption processes

in densely packed systems. These inter-particle or

9. Self-generated Stochastic Heating in an RF dependents effects may be important in particle solar

Discharge collectors, packed and fluidized beds combustors,

AJ. Lichtenberg M.A. Lieberman deposited soot layers, soot conglomerates and microsphere insulation.

The purpose of the project is to study electron heat- Particle sizes that range from very small, in the

ing mechanisms in plane parallel, radio frequency Rayleigh scattering regime, to the very large, in the

(r.f.) discharges. These discharges are used exten- geometric scattering regime, are considered.

sively by industry for surface modification of Analytical predictions of inter-particle effects in scatelectronic and mechanical materials. The energy tering and absorption are derived using electromagdeposition in these discharges is not well understood. netic theory. Experiments to verify these predictions

In addition to the usual r.f. ohmic heating in the plas are being conducted.

ma interior, stochastic heating at the plasma surface

is believed to play a major role. The dependent theory is developed to predict radiative characteristics of agglomerates of small particles The stochastic electron heating arises from successive such as those encountered in flames and combustion

decorrelated reflections of electrons with the oscillat- systems. The radiative characteristics of soot coning sheath near the surface of the discharge. By ex- glomerates are expressed in terms of effective

amining the dynamics of the electron collisions with diameters, which will be convenient in the optical

the sheath, a mapping is derived that describes the diagnosis of particulates in combustion systems.

electron motion. For high frequency (frequency ex- Analytical predictions for soot conglomerates of difceeding 50 MHz), the electron motion is found to be ferent morphologies (straight chains, random

stochastic rather than adiabatic and heating occurs. clusters, and fractal clusters) are obtained and comA Fokker-Planck equation is used to calculate the pared with experimental data.

electron energy distribution, which is shown to be

non-Maxwellian. A simulation model of the discharge, using self-consistent physical constraints gives UNIVERSITY OF CALIFORNIA, DAVIS results in agreement with the analytical theory. Elas- UNIVERSITY OF CALIFORNIA, DAVIS

tic collisions will extend the stochastic heating to Department of Mechanical Engineering $94,000

lower frequencies. Davis, CA 95616 06-B

87-3

Power is deposited in a radio frequency discharge by

three mechanisms: (1) ohmic heating of electrons; (2)

stochastic heating of electrons by reflection from 11. Structure and Stabilization of Premixed and

moving sheaths; and (3) acceleration of ions through Diffusion Flames

sheaths and out of plasma. We are measuring the im- C.K Law

portance of each of these mechanisms in an argon discharge of a range of pressures, powers; and r.f. The program aims to gain fundamental underfrequencies. A typical discharge has pressure 3 standing on the structure and stabilization of

mTorr, power 100 watts, and frequency 13 Mhz. In premixed and diffusion flames. The program involves

this regime, we predict that 95% of the electron heat- both theoretical and experimental phases, and coning occurs stochastically. sists of three components, namely (1) Studies of the

stabilization mechanisms of both premixed and difEngineering Research 5 1988
fusion flames in mixing-layer-type flows, with em- phenomena and models for prediction of transport

phasis on the basically elliptic structure of the leading processes by theoretical and experimental means.

edge of the flame which controls flame holding and . edge of which the flame controls flame holding and The validity of stochastic models for single-phase flow

propagation; (2) Studies of the dynamics of stretched vad tochascmode smle-ae

flames due to flame curvature and flow nonunifor- through randomly packed beds was established by

mity, with emphases on the extinction behavior and on demonstrating tha e predicted dispersive enhancesynthesizing existing experimental and theoretical ment of the axial "effective transport coefficient

agrees with measurements found in literature of both results from a unified viewpoint; and (3) Studies of the ee th masurements found terature of both

properties of thermal-diffusional flamefront in- heat and mass transfer. The role of this dispersive properties of .hermal-diffusional .laniefront in- component on the heat transfer was considered in the

stabilities, with emphases on the spinning and secon- pont on e hea transfer was considered i the

dary bifurcation of polyhedral flames. porous Benard problem. Numerical predictions along with corroborative experimental evidence

During the reporting period we have performed a demonstrated that dispersion enhances the net heat

nonlinear analysis of the dynamics of premixed flames transport through the layer, while inertia diminishes

subjected to heat loss and aerodynamic stretching. it If the packed bed is very shallow (low layer thickSpecific cases studied include the adiabatic stretched ness to bed diameter ratio), both effects decrease the

flame, the nonadiabatic unstretched flame with dis- Nusselt number. Dispersion dominates inertia unless

tributed conductive and radiative heat losses, and the porous Prandtl number is order 0.001 or less.

stretched flames with conductive heat loss; these

cases encompass and extend practically all previous team injecton in a porous channel is being studied

theoretical models on this class of nonlinear premix experimentally and theoretically. In the experimental flame phenomena. Explicit expressioons are obtained studies the qualitative behavior of a steam-water infor the extinction statesobtad terface in a porous channel will be analyzed through high speed movies of the two phase flow and interface

We have also experimentally determined the laminar movement. The principal parameters of interest inflame speeds of methane/air mixtures as functions of elude the frequency of the interface movement, the

stoichiometry, pressure, and flame temperature. The shape of two phase region and flow patterns. The

experimental data are then compared with calculated pressure and temperature distributions will be

values using an accurate flame code and by assuming measured along with flow rates of steam and water.

different kinetic schemes. This comparison allows The physical mechanisms causing the observed rapid

the partial validation of two specific schemes. oscillation of the interface between the two phase

region and the subcooled water are being delineated. Extensive theoretical work has also been performed .on the flame behavior with branching-temination A stability analysis will be carried out. Numerical on the flame behavior with branching-termination . . . chain mechanisms. Results show that extinction can modelingwll nclude mechanisms that are important.

occur through either heat loss or chain termination.

The predicted behavior agree well with our experimental data. UNIVERSITY OF CALIFORNIA,

LOS ANGELES

Department of Mechanical, Aerospace, $65,000

UNIVERSITY OF CALIFORNIA, and Nuclear Engineering 06-B

LOS ANGELES School of Engineering and Applied Sciences 88-2

Mechanical, Aerospace and Nuclear $80,000 Los Angele, CA 90024-1597

Engineering Dept. 01-C 13. Studies in the Combustion and Breakup of

School of Engineering and Applied Science 82-6 Transverse Liquid Jets and Fuel Droplets

Los Angeles, CA 90024-1597 A.R. Karagozian

12. Basic Studies of Transport Processes In 12. Basic Studies ofTransport Processes in The present studies are concerned with analytical Porous Media

r.Caton modeling of the processes of deformation, mass loss,

breakup, and burning in liquid jet streams injected

The researh s to b c d a : 1) se transversely into a crossflow of air and in single liquid The research covers two broad areas: 1) single-phase convection in porous media, and 2) two-phase con- fuel droplets present in a convective environment.

vection in porous media. T he objective of this study This multiphase flow study emphasizes the effect of vection in porous media. The objective of this study the internal vortical structure of the liquid on imporis to develop physical understanding of the governing t nteal rta trutu of the liid o impor- tant physical features of these flowfields, i.e., 1) the

incompressible vortex pair flowfield within the crossEngineering Research 6 1988
section of the liquid transverse jet, and 2) the Hill's between different modes, and to generate a workable

spherical vortex within the axisymmetric liquid description of the role of mechanical noise in activadroplet. tion processes. Recent research also indicates that

Since n the of ts i , or e s he the wave turbulent state possesses structure in that it Since the inception of this grant, our efforts have can support new propagating modes. This elasticity

focused on modeling of the deflection, mass loss, and can support new propagating modes. This elasticity of turbulence is a classical analogue of second sound. breakup of the liquid transverse jet in both subsonic uretle s effe aical a calculated for wind

and supersonic crossflow, in the absence of a chemi- r t e i

cal reaction. Inviscid, compressible flow about the el- waves n a stormy sea

liptical cross-section of the jet is solved analytically in In one and two dimensional systems high amplitude

the low subsonic regime and numerically for upstream wave motion can self-focus into long lived structures.

Mach numbers above 03. The TVD method of Har- These soliton-like properties are being studied as

ten is employed for moderate subsonic crossflow regards possible applications to flexing plates and

(03.7) and the methods of Godunov is used at high shells. Of special interest are the thermal properties

subsonic and supersonic crossflows (M0.7). External of the solitons, the role of damping in the formation

boundary layer analysis along the surface of the cross- of the solitary wave, and possible consequences for

section allows determination of an effective drag as- metal fatigue as regards the recently discovered nonsociated with the jet, which balances centripetal propagating soliton.

forces resulting from jet deflection. Mass and

momentum balances performed along the jet, with

and without the inclusion of mass loss due to droplet UNIVERSITY OF CALIFORNIA, SAN

shedding, are then incorporated so that liquid jet DIEGO

trajectories, bow shock penetration, and approximate

breakup location may be calculated. Correspon- Scripps Institution of Oceanograph $ 0

dence of these predictions with experimental results La Jolla, CA 92093 06-C

is quite favorable, especially in that the modeling contains no empirical correlations or adjustable

parameters. Current efforts are focused on the rep- 15. Nonlinear Dynamics in Dissipative Systems

resentation of evaporation, ignition, and burning in H.D.I. Abarbanel

the liquid jet, and on axisymmetric modeling of the

liquid droplet in a convective environment. This work is directed toward the understanding of the

dynamics and nonlinear stability of multi-phase flows

from a Hamiltonian point of view. The Hamiltonian

UNIVERSITY OF CALIFORNIA, formulation of multiphase flow problems will be the

LOS ANGELES first part of the research. As a second part the conDepartment of Physics $ 75,000 servation laws, in addition to energy, for these flows

LosAngeles, CA 90024 06C will be investigated usingmethods originated by 87-3 Sophus Lie and further developed in the past decade

by these flows in hand, the nonlinear stability of particular flows can be investigated using the liapunov

14. Wave Turbulence and Self-Localization In method of Arnol'd and others. The result of this work

Continuous Media will be a set of critera for the stability of free boundS. Putterman ary flows--material surfaces separating phases--under

finite perturbations. Several examples of gravity drive

The goal of this project is to advance our under- flows will be studied.

standing of the response of nonlinear elastic media

driven far from equilibrium. Research efforts are The d tie or visc version of these lws focused between on the competition bulence and build on the dynamical description of these results. A focused on the competition between turbulence and variational principle arising from the consideration of localization and how these processes affect the fate of the evolution of the energy plus all conserved quan- energy which is injected, into a continuous medium, . in the form of wave motidon. ties will be used to provide ranges for the absolute

stability of viscous multiphase flows. This extends the

Regarding turbulence in propagating waves an at- older energy methods often employed in this kind of

tempt is being made to determine the distribution analysis. The addition of other conserved quantities

function for the higher order correlations. Particular allows the exploration of a larger part of the allowed

aims are to describe the build-up of cross-correlations

Engineering Research 7 1988
phase space for the deviations from a chosen flow UNIVERSITY OF CALIFORNIA, SAN

whose stability one wishes to investigate. DIEGO

Institute for Nonlinear Science $78,000

La Jolla, CA 92093 01-C

UNIVERSITY OF CALIFORNIA, SAN 87-3

DIEGO

Department of Applied Mechanics $120,000 17. Parameterization of Intermittent Turbulence

and Engineering Sciences 06-B and the Vorton Method

La Jolla, CA 92093 87-3 EA. Novikov

16. Fuel Droplets Subject to Straining Flow This reseach project involves the study of a new type

PA. Libby, K Seshadri, F.A. of parameterization of small-scale turbulence, which

Williams recognizes the important phenomena of intermittency. The parameterization is based on the theory of inThis research is concerned with the behavior of single termittent relative motion of fluid particles, which

fuel droplets in a well defined, nonuniform flow field. maybe of independent interest. The method of threeAt present our effort is primarily experimental but in dimensional vortex singularities (vortons) is used for

due course will include complementary theoretical the calculations of elementary events in the intermitstudies. The experiments involve determining tent turbulence (breakdown, reconnection and

photographically the trajectories of individual double reconnection of vortex filaments). Thevorton

droplets and in the case of evaporating and/or corn- method may also have applications to some problems

busting droplets the history of droplet diameter. Ex- in aeronautics. Some vorton calculations, including

periments have been completed on heptane droplets cross instability of two perturbed antiparallel vortex

in a counterflowing, nonpremixed flame and in filaments and merging subsequent splitting of vortex

counterflowing streams of isothermal nitrogen. This rings, have been presented at IUTAM Symposium of

second flow was taken up because its relative Fundamental Aspects of Vortex Motion September,

simplicity facilitates data interpretation. The equa- 1987, Tokyo, Japan).

tions of motion are used to determine the forces acting on the droplet along its trajectory. The results

from both experiments indicate that the nonunifor- UNIVERSITY OF CALIFORNIA, SAN

mity of the flow results in significant lift on the DIEGO

droplets. The available theory suggests that this lift Institute for Nonlinear Science, R-002 88,000

can be due to inertia and/or spin. Unfortunately the La Jolla CA 92093 06-C

relevant theories apply to Reynolds numbers small 86-3

compared to unity whereas our droplets encounter

numbers from one to ten. Attempts to correlate our

force data by rational extensions of theoretical predic- 18. The Stochastic Trajectory Analysis

tions are underway and are to present partially suc- Technique (STAT) Applied to Chemical,

cessful. The results from the flame experiments are Mechanical and Quantum Systems

especially interesting in that the droplets not only ex- BJ. West K Lindenberg

perience lift but drag forces considerably larger than

predicted by current engineering correlations when A number of important physical problems are

approaching the reaction zone. The implication is described by dynamical equations containing flucthat aspherical mass loss occurs. tuating parameters. In dealing with such systems one

has until recently been forced to assume that the fluctuations are delta-correlated, i.e. that their spectrum

is white, thus restricting the scales of the spatial and/or

temporal inhomogeneities to be much shorter than

the response scales of the system. This assumption is

often known to be quite unphysical, especially in nonlinear systems in which all scales are present. Of particular interest in this program are applications

involving chemical reactions in fluids in which the rate

coefficients fluctuate due to spatial inhomogeneities

Engineering Research 8 1988
and thermal effects, dynamical processes in solid which lead to an imperfect bifurcation. Recently it

materials in which fluctuations arise due to spatial dis- has been possible, however, to perfect the apparatus

order and thermal effects, and wave propagation in to point where stochastic effects control to evolution

random media in a geophysical context. of the flow.

A number of methods to deal with the problem of cor- Beyond the convective threshold we are interested in

related fluctuations have been developed under this the evolution and stability of various convective patprogram. One of these involves an explicit construc- terns in containers with simple sidewall geometries.

tion of trajectories (STAT). This procedure is par- We expect that our results will help in the developticularly useful when the noise has simple statistics ment of theoretical models for pattern stability.

and can be used to deal with highly correlated noise. A par y i g py A particularly interesting pattern-stability problem The approach has been applied to linear systems occus in aryitre onetion or ertai ~. -~ *. .- ." . . .. . . . occurs in binary-mixture convection. For certain driven by dichotomous noise, multivalued noise, and va . . .' .. , . , . ....... ' values of the parameters of this system, there exist shot noise. Another class of methods relies on pertur- bative. .aproimti. a.roundthewhitenoise . .lmit. ., spatially localized patches of travelling waves of con- bative approximations around the white noise limit . bative approimations around the white noise limit. vective rolls. The existence of these states cannot be

These methods can be applied most fruitfully to sys- explained by the e s te e of e e e wi s laxaton

ters driven by weak Gaussian slightly colored noise, b t e s m o e s r e at n

and have been used to calculate rates of transitions in dynacs, but rather seem to require nonpotential theories. We are studying quantitatively the bistable systems driven by colored noise. wavenumber, frequency, amplitude, and spatial extent of these localized states. This information will

permit a distinction between several competing UNIVERSITY OF CALIFORNIA, theoretical models.

SANTA BARBARA

Department of Physics $124,000

Santa Barbara, CA 93106 06-C UNIVERSITY OF CALIFORNIA,

87-3 SANTA BARBARA

Department of Chemical and $94,000

19. Bifurcations and Patterns in Nonlinear Nuclear Engineering 01-C

Systems Santa Barbara, CA 93106 88-3

G. Ahlers, D.S. Cannell

20. Turbulent Structure in Liquid Streams This project consists of experimental investigations of 2. T S i L Bounded by a Free Surface and a Solid Wall non-linear non-equilibrium fluid-mechanical sys- Bounded by a Free Surace and a Solid Wall

tems, with an emphasis on heat transport, pattern for- S. Baneriee, H. Fenech

mation, and bifurcation phenomena. These issues are being studied in Rayleigh-Benard convection, . This project is a continuation of an ongoing project being studied m Rayleigh-Benard convection, using . J . . . a. using aimed at studying turbulence structure in liquid flows both pure and multi-component fluids. They play an eeen a solid urbuce and a gas-liquid interf

important role in such energy-related issues as crystal be twe e n a so l d surce a n d a gas-liquid interface.

growth from a melt with and without impurities, the The experimental technques used in this study n- .lude three-dimensional laser-Doppler anemometry catastrophic inversion of salt lakes such as the Dead de three-dimensiona aser-opper an tr Sea, energy production in solar ponds, and various with a 30-micron spot size and oxygen-bubble tracing Sea, energy production in solar ponds, and various oceanographic phenomena. with high-speed videos and flash photography. The

LDA system provides detailed three-dimensional

The work utilizes computer-enhanced shadowgraph velocity measurements while the oxygen-bubble techimaging to visualize the convective flow patterns. The nique gives flow visualization as well as some velocity

technique can detect the flow field even when the con- measurements. These experimental methods are

vection threshold is exceeded by on 0.1%. In paral- complemented by a numerical approach in which the

lel, high-resolution heat-flux measurements are made full Navier-Stokes equations are being solved by a

with a resolution of 0.05%. Thus, the relationship be- pseudospectral method to provide quantities which

tween the pattern and the heat transport can be are difficult to obtain by flow visualization and singlestudied in great detail point velocity measurement. Both the experimental

and computational techniques have been fully In pure fluids, we are investigating the mechanisms a c developed and tested. for the convective onset. In most physical systems the

flow is initiated by properties of the experimental cell

Engineering Research 9 1988
The initial study focusing on phenomena in the ab- ture representation for redesigns, and is modelled as

sence of shear at the interface has been completed a mixedinteger nonlinear programming problem.

and the results indicate that turbulent "bursts"

generated near the wall give rise to the dominant 4) Redesign for flexibility and controllability New

phenomenon in such a flow. At present, turbulence mathematical models have been developed for opcharacteristics in the liquid when the free surface is tmin lexbility in existing chemical processes and

under various shear rates imposed by co-current and to characterize controllability through speed of

countercurrent air flows are being studied. It is found o a process

that the low-speed streaks and bursts characteristic of 5) Redesign of multicomponent separation sequenwall-bounded shear flow also occur near a free sur- ces - an existing flowsheet and a separation task difface when the shear on it exceeds a critical value. ferent from the original flowsheet are given. The

objective is to modify the flowsheet so as to accomplish the new separation task at minimum cost.

CARNEGIE MELLON UNIVERSITY

Chemical Engineering Department $150,000

and Graduate School 03-A CARNEGIE MELLON UNIVERSITY

of Industrial Administration 854 Mechanical Engineering Department $100,000

Pittsburgh, PA 15213 Pittsburgh, PA 15213 01-C

86-3 21. Strategies for Optimal Redesign In a

Changing Environment

L.T. Biegler, I.E. Grossmann, G.L. 22. Experimental And Theoretical Studies Of

Thompson, A. W. Westerberg Vertical Annular Liquid Jets

N. Chigier, JI. Ramos

As the chemical industry matures it is important to

consider the redesign of existing processes. Redesign The objective of this study is to determine the

problems are harder to solve that "grassroots" dynamics and convergence length of vertical annular

problems because constraints dealing with the exist- jets as a function of the inlet inner radius inlet thicking process need to be considered and determination ness, inlet velocity, inlet flow angle, surface tension,

of optimal modifications in an existing plant general- and turbulence. Another objective is to study the

ly will be quite different from optimal solutions for a start-up and stability of annular liquid jets. The exnew plant. This project addresses the optimal perimental part of the program is being performed

redesign problem through the following areas: with different liquid in order to determine the effects

1) Flowsheet optimization fr proces d n. of the Froude, Reynolds, and Weber numbers and 1) Flowsheet optimization for process design. .

Recent work has led to the combination of rigorous geometry on the convergence and stability of annular

jets. The theoretical part of the research program simulation models for rating process equipment with js. Te tl pt of t r

sophisticated methods for mixed integer flowsheet deals with the development of an implicit finite-dif- sophisticated methods for mixed integer flowsheet ference scheme for studying the dynamics and optimization. For flowsheets with fixed topologies we ference scheme for studying the dynamics and

have also demonstrated the potential for performing stability of annular liquid jets. The theoretical studies have also demonstrated the potential for performing a b o th s of t tmde n

pr . cess optimay .. and . automaticay. are based on the solution of the time-dependent

process optimay retrofits and automaticallyaxisymmetric form of the Navier-Stokes equations

2) Primal/dual linear (LP) and quadratic program- and account is taken of surface tension and the adming (QP) algorithms. These new algorithms for solv- verse axial pressure gradient which occurs near the

ing LP and QP problems were developed during the annular liquid jet convergence. The results of these

first two years of this project. Computational tests models are being compared with experimental data

showed that codes based on these algorithms were at obtained at Carnegie Mellon University and at the

least 10 times as fast as currently available codes, and Westinghouse R&D Center.

they were especially effective for problems having they ere espcialy ective for pro ms having Experiments have been carried out on annular liquid more constraints than variables. curtains with an initial radius of 50 my and initial sheet

3) Redesign of energy management systems. A thicknesses of 0.5 and 1.0 mm. Three Froude numbers

screening and optimization approach is being have been studied: 1.27,4.27, and 8.87 by variations of

developed for the redesign of heat exchanger net- the liquid flow rate. Pressure within the curtains was

works. The screening is based on parametric solutions varied progressively from 0 to 3 Pa. Several flow

for energy cost, area and structural modifications. regimes were found: a) non-pressurized, b) presThe optimization is performed on a novel superstruc- surized, c) oscillating, and d) punctured. Curtain

Engineering Research 10 1988
shape and convergence length were determined by UNIVERSITY OF CHICAGO

photography. Velocity in the liquid curtain was The Enrico Fermi Institute $150,000

measured by Laser Doppler Anemometry. The varia- Chicago, IL 60637 06-C

tion of liquid film thickness with axial distance was 87-3

determined. Good agreement was found between

predictions and experiments. 24. Fundamentals and Techniques of

Nonimaging Optics for Solar Energy

UNIVERSITY OF CHICAGO Concentrton

Department of Chemistry $78,000

Chicago, IL 60637 064C Nonimaging optics departs from the methods of tradi86&3 tional optical design to develop instead techniques for

maximizing the collecting power of concentrating ele23. Topics in Finite-Time Thermodynamics ments and systems. Designs which exceed the conRS. Beny centration attainable with focusing techniques by

factors of four or more and approach the theoretical

The objective of this research is the analysis in ther- limit are possible. This is accomplished by applying

modynamic terms of the performance of systems and the concepts of Hamiltonian optics, phase space conprocesses subject to time or rate constraints. Part of servation, thermodynamic arguments, and radiative

the research deals with developing methods for con- transfer methods. In the early nonimaging designs the

ducting anaylyses, such as emerged from the introduc- might edifice of aberration theory was dismantled and

tion of a suitable metric in the space of replaced by a single key idea. According to this, maxthermodyanmic variables and the evaluation of path imum concentration is achieved by ensuring that rays

lengths with that metric. The lengths so obtained have collected at the extreme angle for which the conbeen shown to be directly related to the dissipation centrator is designed are redirected, after at most one

associated with the path. Another piece of recent reflection, to form a caustic on the absorber. This

work at this basic level just completed under this principle proved sufficiently elastic to accommodate

project is an attempt to introduce a variational for- most boundary conditions in two dimensions (i.e.,

mulation of irreversible heat transfer and diffusion, linear geometry). Ideal solutions in three dimensions

which is intended to apply in nonlinear as well as have also been formulated. Our work on vector flux

linear situations. has led to a reexamination of the foundations of

radiometry with emphasis on observable effects. Our

The other aspect of this research is the application of theoretical work on nonimaging designs has led to

the general methods to the analysis of specific systems demonstration of ultra-high flux from sunlight which

of current interest. During the initial period of the exceeds previous results by substantial factors.

project, the stopping of a beam of atoms by absorption and reemission of laser light was analyzed and the

entropy changes in the process were evaluated. The

reduction in entropy of the atomic beam due to cool- CLARKSON UNIVERSITY

ing and stopping is compensated a thousandfold over Department of Chemical Engineering $58,000

by the increases in the entropy of the light due to ran- Potsdam, NY 3676 01-C

domization of the phase, the polarization and espe- 88-3

cially the propogation direction.

25. Droplet Motion in Numerically Simulated

Turbulence

J.B. McLaughlin

The primary goal of the research is to obtain information about the dispersion of aerosol size droplets and

particles in a turbulent channel flow. It is assumed that

the flow is vertical so that aerosols do not sediment

onto the channel walls. The behavior of aerosols in

the viscous wall region is of particular interest since it

has been suggested that shear induced lift forces may

Engineering Research 11 1988
be very significant in this region. The approach invol- the remainder of the contract period include compleves numerical integration of the aerosol particle equa- tion of the evaluation studies with water followed by

tion of motion to obtain the trajectories of the droplets additional evaluations with methanol or an initiation

or particles. In order to perform such calculations, of studies on alternative refrigerants.

the undisturbed (by the particles) velocity field of the

fluid is needed and this is supplied by a direct numerical solution of the Navier-Stokes equation using pseu- UNIVERSITY OF CONNECTICUT

dospectral methods. The fluid velocity is used to Department of Mechanical Engineering $65,000

evaluate the Stokes drag force and the Saffman lift St , 06 01-A

force in the aerosol particle equation of motion. By C 8

comparing runs in which the lift force is dropped with

runs in which it is retained, one can obtain information about the importance of shear - induced lift on 27. Micromechanical Viscoplastic Stress-Strain

aerosol motion. Model with Grain Boundary Sliding

E.H. Jordan

COLORADO SCHOOL OF MINES The goal of this research is the development and

Department of Chemical Engineering $49,000 verification of a model of the time and history dependand Petroleum Refining 03-B ent viscoplastic deformation behavior of polycrystalAGolden CO 80401 872 line metals. Single grain behavior will be derived by summing postulated slip behavior on crystallographic

slip systems. Multi grain behavior will be obtained by

26. An Automated Flow Calorimeter for Heat summing deformation occurring in different grains

Capacity and Enthalpy Measurements at while accounting for grain interaction through a self

Elevated Temperatures and Pressures consistent micromechanics approach. The model will

V.F. Yesavage also represent grain boundary sliding through the use

of a solution recently published by T. Mura.

The need for thermal property data at process condi- tion has been well documented in applications such High temperature experiments will be used to verify tion has been well documented in applications such developn has el of a doment ericaly inert rerigrants the model. Single crystal properties used for input to as development of atmospherically inert refrigerants and design of petrochemical and synfuel plants. s the model will be determined experimentally for Hasand esign of petrochemical and syuel plants.- As telloy-x. Using these properties, the behavior of such, the primary objective of this work is to construct poyrystal Hasteoy-x i be preite an then

an automated flow calorimeter to measure isobaric polycrystal Hastelloy-x will be predicted and then an automated flow calorimeter to measure isobaric a i . he c te , . ... , ,, . , ... compared with experiments. These tests constitute a heat capacities and enthalpies of vaporization over comared with et h t o

the range 0-30MPa and 300-700K with an anticipated ccal test for the theory

accuracy of 0.1%. The method of measurement is an The model will not only predict the viscoplastic

adiabatic electrical power input technique with a uni- response of polycrystals but also will allow metallurque calorimeter design utilizing a concentric gical findings usually stated in crystallographic terms

coil/radiation shield structure which minimizes heat to be more directly incorporated into the model. The

loss errors and simplifies the replacement of plugged explicit calculation of grain boundary sliding will help

components. Flow generation is accomplished with a illuminate the role played by grain boundary sliding

precision Ruska pump eliminating the need for on- in the overall deformation during complex load hisline flow rate measurement. In addition, the tories. Grain boundary sliding deformation plays an

proposed instrumentwill be fully automated minimiz- important role in material damage and the model

ing the need for high skilled operators which had pre- should be useful in life prediction under complex variviously been a severe limitation with this type of able temperature conditions.

instrument. The work will be done with the cooperation of EnAssembly of all hardware and implementation of the gineering Science Software, Inc. working under a renecessary software was completed within the past lated contract. Manufacture of single crystal

year. In addition, water was used as a heat capacity specimens will be done by Pratt and Whitney, Inc.

standard to evaluate overall system performance.

Preliminary indications are that the apparatus is

operating near expectations (+/- 0.2%) although

some additional hardware refinements maybe necessary achieve the design goals of +/- 0.1%. Plans for

Engineering Research 12 1988
CORNELL UNIVERSITY DARTMOUTH COLLEGE

Sibley School of Mechanical and $100,000 Thayer School of Engineering $ 0

Aerospace Engineering 01-C Hanover, NH 03755 01-C

Ithaca, NY 14853 88-3 86-3

28. Experiments in Turbulent Mixing 29. Subcooled Sprays in a Vapor

Z. Warhaft Environment-Tests of the Two-Fluid Model

for Two-Phase Flow

This project is concerned with experimental studies G.B. Wallis, HJ. Richter

of scalar mixing in fully developed turbulent flows, a

subject relevant to our understanding of chemical The "separated" or "two-fluid" model for two-phase

reactions, combustion and environmental pollution. flow is being used to describe the behavior of a subMixing in both homogeneous and inhomogeneous cooled spray in a vapor environment. Detailed

turbulence, with and without the effects of buoyancy measurements will be used to determine viable forms

is being examined. of the "interaction" terms describing mass, energy and

momentum transfer between the phases. The overall The first experiment concerns scalar dispersion and m t b .T r

a shearless .in "second order, . mixing lr purpose is to advance the stateof-the-art of basic mixing min a shearless second order mixing layer .

analytical and computational tools for describing two- Here various turbulence generating grids are p .lti

designed so that large turbulent eddies on one side of

the flow mix and diffuse with smaller eddies on the In the two-fluid model each phase satisfies the usual

other side of the flow. The porosity of the grid is such set of equations of conservations of mass, momentum

that the mean flow remains constant across the grid and energy with the influence of one phase on the

and hence there is no mean velocity shear or tur- other appearing as "interaction terms" that couple the

bulence production. Thus, the spreading rate in the two sets. While much effort has been devoted to writmixing regionis determined solelyby turbulence - tur- ing down various forms of equations and discussing

bulence interactions. This flow, although in some how they can be obtained by averaging the basic conrespects more fundamental than the turbulence servation laws for each phase, few workers have acmixing layer with shear, is poorly understood. The tually applied them to specific situations. It is likely

flow is unusual in that it is homogeneous in the main that useful and reasonable simple expressions can be

but has large scale intermittence and the turbulence devised to represent coupling effects when the flow

is inhomogeneous. Scalar dispersion from the thin pattern is clearly defined: for instance, a dispersion

thermal line source placed in the center of the flow is of one phase in the other. Previously, physicallyalso being studied. based formulations have been applied to a onedimensonal representation of fluidized beds, The second main experiment is concerned with scalar dimenonal represen n of f d sedimentation, and "mist-lift' processes or the two- mixing in stably stratified decaying grid generated tur- processes or the two- and three-dimensional modeling of sprays in gases bulence. A linear temperature (density) gradient i and three-dmensional modeling of sprays in gases

formed at the entrance to the plenum chamber of the and pares interacng with a fluid.

wind tunnel and then the flow is passed through a tur- This project concerns a dispersed flow regime in

bulence generating grid. The negative buoyancy which heat and mass transfer play leading roles: the

causes the heat flux to decay (and in some cases condensation of vapor on a subcooled spray of

reverse sign) and there is a complex interaction be- droplets. Analysis of this regime requires the intween the various components of turbulent kinetic clusion of significant interaction terms in all of the

energy and the potential energy. Single and multiple conservation laws, thus providing a comprehensive

line source dispersion experiments on mixing across test of the theory. Complementary analytical and exsharp temperature steps, with and without buoyancy, perimental work are planned. The experiments are

are being attempted. intended to build up to realistic complexity (e.g., a

drop size spectrum in the spray, variations in spray

flux as a function of angle) while keeping the flow pattern sufficiently well-defined to be amenable to

theoretical representation.

Engineering Research 13 1988
ENGINEERING SCIENCE G. A. TECHNOLOGIES, INC.

SOFTWARE, INC. P.O. Box 85608 $ 0

Smithfield, RI 02917 $ 47,000 San Diego, CA 92138-5608 06-C

01-A 85-3

88-3

31. Higher Dimensional Nonlinear Dynamics

30. A Micromechanical Viscoplastic JM. Greene, J. Kim

Stress-strain Model with Grain Boundary

Sliding The goal of this project is to explore how the methods

K.P. Walker of nonlinear dynamics can be applied to ever more

complex systems.

The aim of the project is to develop a viscoplastic con- The moder theory of nonlinear dynamics is, to a

stitutive model, with accompanying FORTRAN large extent, the understanding of the way in which

software, to model the deformation behavior of computational results can be used to gain insight into

polycrystalline metals comprised of an aggregate of the nature of chaotic and turbulent systems. A

fcc single crystal grains whose crystallographic axes property of such systems is that two different orbits

are oriented at random. The single crystal grains are that are crudely indistinguishable are generally quite

assumed to be spherical and are modeled with an different in their detailed behavior. Thus, a single anisotropic viscoplastic theory based on crystal- orbit, or realization, contains a confusing mixture of

lographic slip along the octahedral and cube slip uninteresting detailed information, and usefully directions of the fcc metal. The overall response of the generalizable information. The most easily obtained,

polycrystalline aggregate is assumed to be isotropic additional exact information that computers can

and is deduced from the single crystal response by provide comes from the solution of equations

means of a self-consistent method. The effect of grain linearized around a given orbit. The objective of this

boundary sliding between the grains is being modeled program is a thorough understanding of the informain the self-consistent formulation to assess the impor- tion available through linearization.

tance of including this mechanism in the overall

response of the polycrystalline material. This information mostly falls under the key words of

Lyapunov exponents and directions. That is, this Experimental tests on single crystal specimens of the study emphasizes the information available in the

superalloy Hastelloy-X are being run at the Univer- rates and directions of separation of nearby orbits, or

sity of Connecticut to determine the material con- realizations. The methods are being developed and

stants in the single crystal constitutive model. The tested using the Lorenz model. The knowledge overall response of the self-consistent model of the gained this way is being applied to the Kuramotopolycrystalline aggregate will then be theoretically Sivashinsky equation, a simple partial differential

determined and compared with experimental results equation with chaotic solutions. The object is to

from isotropic specimens of polycrystalline Hastel- develop representations in which these solutions can

loy-X be most simply expressed.

The FORTRAN software will allow metallurgical and

micromechanicalwork reported in the literature to be

easily embedded in a constitutive (stress-strain) UNIVERSITY OF HOUSTON

framework for analyzing the overall deformation Department of Mechanical Engineering $125,000

response of polycrystalline metal aggregates under Houston, TX 77204-4792 01-C

thermomechanical loading conditions. 87-3

32. Comparative Study of the Vorticity Field in

Turbulent Flows: Theory, Experiments,

Computations

A.KM. Hussain

Fluid turbulence affects many energy systems. On the

negative side it contributes to noise generation and

vibrations of key system components, while on the

Engineering Research 14 1988
positive side it serves to enhance mixing and heat As a complement to the experiments, an analytical

transfer. These are essentially empirically established model for film boiling heat transfer that accounts for

facts. On the theoretical side over the years relative- turbulent flow in the liquid and vapor layers flowing

ly slow progress has been made toward a better un- over the heater will be developed. Existing laminar

derstanding of such flows on the fundamental level. flow models will be modified to include turbulence efA barrier to progress has been the difficult nature of fects. There is some evidence that flow of high

the equations governing the behavior of fluids. It has velocity, subcooled liquids degenerates into "froth" in

been recognized for a long time that the mathemati- the normal film/transition regions. Insight into the

cal difficulties could be mitigated to some extent if one nature of these flows will be sought using high speed

had a prior knowledge of the vorticity field accom- video, and, if possible, models will be developed to

panying the velocity field. The present proposal will predict heat transfer during such flows.

take advantage of progress in instrumentation

developed under other auspices aimed at measuring

vorticity directly. IDAHO NATIONAL ENGINEERING

A newly constructed nine-wire probe is expected to LABORATORY

measure the components of vorticity with a resolution Applied Optics $133,000

of about one to two millimeters. The direct measure- Idaho Falls, ID 83415 06-A

ment of vorticity simultaneously with velocity will 85-3

permit the evaluation of the merits of a recent

hypothesis that the observed large-scale coherence in

turbulent flows is induced by a spontaneous, sym- 34 In-Flight Measurement of the Temperature

metry breaking onset of helicity. While helicity, that of Small, High Velocity Particles

is the scalar product of vorticity and velocity vanishes R. Finke

in the mean, its mean square value need not vanish.

How fluctuations would give rise to an observable Knowledge of in-flight particle temperature is funhelicity, and how given its onset it would affect the damental to understanding particle/plasma interaclarge-scale coherence of turbulent flows is a con- tons the physical and/or chemcal processing of

troversial theoretical issue. At this point, ultimately fine powders. The measurement of in-flight particle

only a recourse to an experiment can resolve the con- temperature is based on a two wavelength pyrometry

troversy. technique. In addition, simultaneous particle size is

obtained by a light scattering technique. The requirement of coincidence between sizing and pyrometry

signals insures that only particles for which tempera- UNIVERSITY OF HOUSTON ture data are available will be sized. The technique

Department of Mechanical Engineering $78,000 has been demonstrated on laboratory scale plasma

Houston, TX 77204-4792 01-B torches. The influence of particle size, injection rate,

88-3 torch power, etc., are currently being examined in

detail. In addition methods of simultaneously obtain33. High Flux Film and Transition Boiling ing particle size, velocity and temperature are under

L.C. Witte development.

This project is one of six projects comprising a colThe potential for altering the boiling curve through laborative research program with the Massachusetts

the effects of high velocity and high subcooling will be Institute of Technology.

investigated in this study. This investigation is based

on evidence that the transition region can be avoided

when very cold liquids are boiled at high velocities.

An experimental flow loop capable of circulating liquids up to 8-10 m/sec will be equipped with a chiller

so that liquid temperatures down to 3-4 C for water

and -32 C for Freons are achievable. Boiling data

along with visual observations of water and Freon-113

boiling from a small electrically heated cylinder in

crossflow will be obtained.

Engineering Research 15 1988
IDAHO NATIONAL ENGINEERING IDAHO NATIONAL ENGINEERING

LABORATORY LABORATORY

Sensors and Diagnostics Group $183,000 Energy and Systems Technology Group $262,000

Idaho Falls, ID 83415 03-B Idaho Falls, ID 83415 06-C

83-5 87-1

35. Nondestructive Characterization of Fracture 36. Modeling of Thermal Plasma Processes

Dynamics and Crack Growth V.H. Ransom, J.D. Ramshaw

A4. Johnson, BA4. Bama, RIT.

Allemeir Optimization of thermal plasma processing techniques will require a better understanding of the spaceThe purpose of this research is to develop instrumen- and time-resolved flow and temperature distributions

tation and models to measure and predict the emis- in the plasma plume and of the interaction between

sion and interaction of ultrasound from growing the plasma and a particulate phase. This research is

cracks in engineering materials and to investigate directed toward the development of a comprehensive

methods of sensing the properties of growing cracks. computational model of thermal plasma processes

A high speed digital acoustic emission (AE) data ac- and plasma-particle interactions capable of providing

quisition system is being developed and applied to such information. The KIVA computer code was

fracture mechanics experiments that are part of the adopted as a starting point for the model development

Elastic-Plastic Fracture Analysis program at INEL since it already contains many of the necessary feaand the Modeling and Analysis of Surface Cracks tures, including implicit numerics for efficient conprogram at the Massachusetts Institute of Technol- putation of acoustic waves and diffusion,

ogy. In addition, numerical methods are being used multicomponent gas fow with real gas effects, turto model the interaction of acoustic emission stress bulence models, kinetic and equilibrium chemical

waves with real crack geometries. reactions, and discrete particles coupled to the gas

The n AE s dete mis b g d d ad flow. Work is in progress to develop and incorporate The AE detection system is being developed and is y permit cocapable of detecting and digitizing AE signals with a the additional subodels necessary to permit co plete quantitative plasma processing simulations. In larger bandwidth and with less dead time than in con- pe qe p a p tin n

ventional systems. This will allow improved resolu- particular, models are needed for convective and

radiative heat losses and for a variety of plasma-par- tion in detecting the locations of the sources of

emissions and in discriminan betweon ating prcessesat, including evaporation

sources. Automatic analysis methods are being condensation, nucleation, agglomerations, and sources. Automatic analysis methods are being coalescence. Modeling these latter processes will be developed for source location and source identifica- the most challenging task from a physical point of tion for each of the large number of acoustic emission e the representation will require major

events received in a typical fracture mechanics experi- view, and their representation will require major m ents. Other iwrr j design,1r modifications to and extensions of the KIVA particle ment. Other work includes transducer design, model.

transducer calibration, generalized ray theory

analysis (Green's functions), source location algo- This research is closely coordinated with other plasrithms, and inverse source identification algorithms. ma processing programs both within the Department

of Science and Technology of the Idaho National En- Models of the ultrasonic field/crack interaction are of Sience and Tenoloy ao the Idaho National nbased on a numerical (finite element) solutions to the n L

stitute of Technology. partial differential equations (PDE) describing the sttute o

system. In the finite element model, a source of

acoustic emission is modeled by changing boundary

conditions and the ultrasonic fields that propagate

from the source to a receiver are calculated. All mode

conversions are automatically included in the numerical solution to the PDE with the boundary conditions

of the system. These boundary conditions include the

geometry of the macrocrack near the source of acoustic emission and thus calculate receiver signals which

include effects that cannot be calculated using

generalized ray theory.

Engineering Research 16 1988
IDAHO NATIONAL ENGINEERING IDAHO NATIONAL ENGINEERING

LABORATORY LABORATORY

Materials Technology Group $439,000 Materials Technology Group $319,000

Idaho Falls, ID 83415-2218 01-A Idaho Falls, ID 83415 06-A

816 85-3

37. Elastic-Plastic Fracture Analysis Emphasis 38. Experimental Measurement of the

on Surface Flaws Plasma/Particle Interaction

W.G. Reuter, W.R Lloy4 C.B. Shaw, S.C. Snyder, L.D.

S.Graham Reynolds

The objective is to improve design and analytical tech- The objective of this research is to quantitatively

niques for predicting the integrity of flawed structural describe the heat mass, and momentum transfer ascomponents. The research is primarily experimental, sociated with metallic or oxide particles immersed in

with analytical evaluation guiding the direction of ex- thermal plasma environments. In order to characperimental testing. Tests are being conducted on a terize the interaction between plasma constituents

materials (a modified ASTM A-710) exhibiting a and particles, the development of new methods to

range of fracture toughness but essentially constant determine plasma flow velocity and species composiyield and ultimate tensile strength. As test tempera- tions are being developed. Holographic interture increases, the specimen configuration-fracture ferometry is currently being considered for plasma

toughness relationship complies initially with require- flow velocity determination and planar laser induced

ments for linear elastic-fracture mechanics and ex- fluorescence is being considered for compositional

tends beyond the range of a J-controlled field. measurements adjacent to particle surfaces. Using

Presently, compact tension and bend specimens are these advanced techniques, temporal and spatially

being used to develop state-of-the-art fracture resolved distributions of the chemical and physical

mechanics. These results are used to make con- properties of the plasma/particle environment will be

parisons with data developed from specimens con- determined. Since this research is performed in coltaining surface cracks. laboration with research at Massachusetts Institute of

These comparisons are presently underway for 6.4 Technology, the resulting experimental data will be These comparisons are presently underway for 6.4 ^ ^ ^ ^ ^ ^ theoretical models used

and 12.7 mm thick surface- flawed specimens. Metal- used to validatea and theoretical models used

lographic techniques are being used to measure crack for thermal plasma processing and for predictions tip opening displacement and remaining ligamentsize * relating to optimal torch and fixture design criteria. tip opening displacement and remalningligamentsi^ Experimentsare currently being performed in two

for comparison with analytical models. Other techni- Experiments are currently being performed in two

ques including microphotography and the replicating plasma torch designs, a constricted nozzle torch and

ques including microphotography and the replicating an expanding nozzle torch. Input power dissipation of the crack tip region, for future metallographic ex- an exaning from 5 to 180 kW being are studied.

amination, are being used to complement the above levels ranging from 5 to 180 kW are being studied

measrements to enti lmt an apablte o These torch designs produce a representative plasma measurements to identify limits and capabilities of e f idsrapa- technique .each Moire interferometry techniques are characteristic of those employed for industrial plas- each technique. Moire interferometry techniques are

being used to evaluate and quantify the deformation ma proces

in the crack region. These data are being used to experimentally measure J and CTOD for standard (CT

and SENB) specimens as well as for specimens containing surface cracks.

The above tests have been supplemented by using

specimens fabricated from aluminum (dimple rupture only) and titanium. The titanium specimens are

being used to study the fracture behavior and the

ability of existing models to predict failure for weldments. Moire interferometry techniques are being

used to study the local constitutive behavior and the

fracture process at the crack tip region of the weldment.

Engineering Research 17 1988
IDAHO NATIONAL ENGINEERING UNIVERSITY OF ILLINOIS

LABORATORY Coordinated Science Laboratory $120,000

Materials Technology Group $450,000 Urbana, IL 61801 03-A

Idaho Falls, ID 83415 03-A 88-3

85-3

40. Model Building and Control of Large Scale

39. Integrated Sensor Model Development for Systems

Automated Welding T. Basar, P. Kokotovic

H.B. Smartt, JA. Johnson

The research agenda laid out in this proposal aims at

The objectives of this research are (1) to develop a comprehensive study of some fundamental issues

models of the physical phenomena occurring in the arising in the modeling, control and coordination of

gas metal arc welding process suitable for real-time deterministic and stochastic large scale systems. Our

process control, (2) to develop sensors and signal research plan is first to extend the relevant existing

processing algorithms for arc welding processes in- theories and methodologies in novel directions,

cluding optical and ultrasonic techniques, and (3) to covering areas such as (i) model simplification

integrate the above models and sensing with advanced through decomposition and aggregation, (ii) temcontrol methodologies. This project is part of a col- poral and spatial hierarchies, (iii) goal-oriented

laborative research program with the Massachusetts hierarchies and multiple decision layers, and (iv) conInstitute of Technology. trol and coordination of large scale systems based on

(probabilistic multimodeling. Following this, we will

A fundamental model of the gas metal arc welding develop a new framework which will allow for disprocess has been developed which considers wire tributed and interactive model building and control,

melting and heat and mass transfer to the base metal. where both structural and decision making hierarThis model is being extended to account for droplet chies evolve over time. It unique characteristic is that

detachment modes and the dynamic aspects of heat the two independent tasks - modeling and control -

and mass transfer through the arc. treated heretofore independently, will now be

Sensing of the weld pool solid/liquid interface loca- designed to evolve in parallel and complementary to

tion is being developed using noncontract each other.

transducers. Signal generation is by use of laser pulses directed on the weld pool. Signal analysis/pattern

recognition techniques are being developed based on UNIVERSITY OF ILLINOIS

AI methods for automated measurements. Department of Chemical Engineering $106,000

Independent control of heat and mass input to the Urbana, IL 61801 01-C

weld has been demonstrated. Sensing algorithms to 8

characterized droplet transfer mode by acoustic and

electrical signals have been developed. Control of 41. Gas-Liquid Flow in Pipelines

weld bead cooling rate during gas metal arc welding TJ. Hanratty

has been demonstrated wherein the cooling rate has

been varied independently of the weld reinforcement. Research is being conducted to obtain a better underThis has allowed near steady-state cooling rates to be standing of gas-liquid flow in horizontal and vertical

achieved during weld start-up, an important factor in pipelines. The goals are (1) to develop methods to

reducing weld defects. predict when slug flow will exist in horizontal gas-liquid flows, (2) to obtain a better understanding of the

interfacial wave patterns in stratified gas-liquid flows,

(3) to obtain improved predictive methods for

horizontal and vertical annular flows. Vertical flow

experiments are being conducted in pipelines with

diameters of 3/4 in., 1 1/2 in., and 2 1/4 in. The

horizontal flow facility, which has pipelines of 1 in., 2

in., and 4 in., was completely renovated during the

past year so that it can operate with a wide range of

liquid viscosities and at inclinations of 2 degrees.

Engineering Research 18 1988
Three mechanisms have been identified for the initia- b. Forced convection behavior of viscoelastic fluids

tion of slug flow. Slugs can originate from the growth in laminar and turbulent flows through rectangular

of infinitesimal long wavelength disturbances or form channels.

small wavelength disturbance which develops into T d win r n n To date the following results have been found: large wavelength disturbances through a non-linear

energy transfer process. The possibility of their initia- a. High concentrations of the aqueous hydroxyethyl

tion by entry disturbances can be predicted by the cellulose solutions yield higher values of the boiling

development of necessary conditions for the existence heat flux than found with deionized water when comof slugs. pared at the same wall-to-fluid temperature difference. In contrast, aqueous polyacrylamide Interfacial stress in stratified flows has been as- f . In , aques sociated with large amplitude waves which are solutions yield lower values of boiling heat flux than sociated with large amplitude waves which are found with deionized water when compared at the generated by a Kelvin-Helmholtz 6 mechanism. Inpar- found with deiozed water when compared at the , ~. .. ' . .. ~ *. . . same wall-to-fluid temperature. Detailed studies of ticular, it has been shown that the stress is uniquely sae wd . the bubble dynamics using high speed video equip- related to the wave steepness for wide range of pipe the bubb dynamics using high speed video equip- diameters liquid viscositiesment and are being carried out to establish a rational basis diameters and liquid viscosities, for the observed behavior. for the observed behavior.

Techniques have been developed to measure the rates . The forced convection measurements in the rec- , . * *** .. * . j .* i in b. The forced convection measurements in the rec- of atomization and deposition in vertical annular flow. tangular channel, taken together with earlier circular A theoretical understanding of these rate processes isth earer circular being thr obtained h msof we p- tube measurements, lead to the following conclusions: being obtained through measurements of wave patterns and droplet motions. These measurements are 1. The friction-factor and heat transfer behavior of

being used to develop better predictive methods for purely viscous and viscoelastic fluids is the same

entrainment. under fully developed laminar pipe flow conditions.

Previous measurements of entrainment for air-water 2. The heat transfer performance of viscoelastic

flow in a horizontal one inch pipe have been extended fluids in laminar flow through rectangular channels is

to include 2 inch and 4 inch pipelines. It is found that considerably higher than predicted for purely viscous

an understanding of the effect of pipe diameter on fluids, although the friction factor is predicted by the

entrainment depends on understanding the impor- purely viscous analysis.

tance of the gravitational settling of drops. of r o o ro 3. In turbulent flow through circular and noncircular channels many, but not all, viscoelastic fluids are

drag reducing. In particular, aqueous Carbopol soluUNIVERSITY OF ILLINOIS AT tions are viscoelastic but show no drag reduction.

CHICAGO

Energy Resources Center $ 74,000

Chicago, IL 60680 01-B UNIVERSITY OF ILLINOS AT

85-2 CHICAGO

Department of Civil Engineering, $54,000

42. Heat Transfer to Aqueous Polymer Solutions Mechanics and Metallurgy 01-A

J.P. Hartnett Chicago, IL 60680 88-1

The goal of the research is to study the fluid mechanical and heat transfer behavior of viscoelastic aqueous 43. Continuous Damage Mechanics II

polymer solutions. The ultimate objective is to D. Krjcinovic

provide a basis for predicting the performance of such

fuids. At the present time, two basic investigations The current state of development of the theory dealfare underwayt the p t t , to bc is ing with the brittle response of solids is characterized

*~are underway.~ by a substantial arbitrariness reflected in a host of

a. Pool boiling behavior of aqueous solutions of the conflicting analytical models. The main objective of

two high molecular weight polymers, hydroxyethyl this research is to formulate a comprehensible concellulose and polyacrylamide and a comparison with tinuum damage theory based on the improvements in

pool boiling performance of deionized water. the understanding of the underlying phenomena

gained through experiments and application of

micromechanics. Even though they are very useful

micromechanical models typically require manipulaEngineering Research 19 1988
tions of very large databases causing significant com- The theoretical developments will be tested exputational complexities and presenting potent dis- perimentally on pilot scale equipment in the

couragement for their application in engineering laboratory. Vibrational control will be implemented

practice. by introducing forced periodic oscillations in the

.A1 . input concentrations and flow rates. The effects of The proposed model should retain the simplicity of a i c a f

continuum theory without loosing the physical in- mutiplevibratingputswllbeanalyzed

sights provided by the micromechanical studies tributions of the phase relationships between the forcOnce th ceck on some ing functions of various inputs will be investigated.

Once the theory has (been checked on some This study will provide techniques for improving benchmark problems (for which the pertinent benchmark problems (for which the pertinent selectivity and yield in complex chemical reactions micromechanical data are available) it willbe possible mirtomechanic a v stt ) idposs and for reducing the overall control effort in reactor

to study more complicated problems. configurations used in the industry. used in the industry.

The principal tasks of the initial phase of the project

are: to select representative fluxes and affinities, to

formulate a reasonable damage and failure surfaces JET PROPULSION LABORATORY

and investigate the applicability of the normality California Institute of Technology $78,000

property. Initial effort will be focused on the perfect- Pasadena, CA 91109 03-B

ly brittle response of solids such as concrete, rocks 86-3

and ceramics.

45. Applications of Molecules as High

ILLINOIS INSTITUTE OF Resolution, High-Sensitivity Threshold

~~~~~~~~~TECHNOLOGY rElectron Detectors

A. Chuojian, S.H. Alajajian, OJ. Department of Chemical Engineering $ 80,000 Orient

Chicago, IL 60616 03-A

84'3 Measurements and theoretical calculations are carried out of electron attachment cross section oA (e)

44. Vibrational Control of Chemical Reactors: and rate constants in molecules at electron energies

Selectivity Enhancement, Stabilization and below 200 millielectron volts (meV). Measurements

Improvement of Transient Behavior are carried out at extremely high energy resolution (5-

A. Cinar 8 meV, FWHM) using the krypton photoionization

technique developed at JPL. This electron energy

The objective of this project is to develop novel ap- region is accessible by no other experimental techniplications of the vibrational control theory to various que, and previously-published JPL results have cleartypes of chemical reactors. From the mathematical ly shown the s-wave threshold behaior in which CA (E)

standpoint, the goal of this research is to analyze the diverges as e' 12. The molecules c-CsF8 and c-C6Flo

effects of fast parametric oscillations on the dynamics have shown extremely narrow, delta-function like

of the systems studied. Research is focused on three widths for attachment of zero-energy electrons. This

areas of application: feature makes them suitable as high sensitivity

threshold electron detectors useful in, for example, (i) Selectivity and yield enhancement in parallel reac- obtaining threshold photoelectron spectra of atoms

tions with desirable and undesirable products. The and molecules. Experimental results in F2

oxidation of ethylene over supported silver catalysts (published), and theoretical calculations in CFCI3

to ethylene oxide and carbon dioxide is used as a test and CC4 (to be published) have shown significant

reaction. discrepancies with calculation and other experiments

(ii) Stabilization of nonadiabatic and autothermal as to energy dependence of the oA (E), and temperatubular packed-bed reactor operation at an otherwise ture dependence of the rate constants. These properunstable steady state. The CO oxidation reaction is ties have bearing on the plasma-assisted etching

used as a test reaction. process, and on soot (and/or electron density) reduction in combustion plasmas. To this end, experimen- (iii) Improvement of transient behavior of non- tal work on attachment to C2 will be initiated,

adiabatic and autothermal tubular packed-bed reac- calculations in CFC13 and CC4 completed, and attors by relocation of system zeros using tachment properties of about six other molecules, curvibrational-feedback control.

Engineering Research 20 1988
rently being tested elsewhere as electron "sinks" or LAWRENCE BERKELEY

soot reducers in combustion plasmas, will be studied. LABORATORY

Applied Science Division $190,000

University of California 06-B

LAWRENCE BERKELEY Berkeley, CA 94720 87-3

LABORATORY

Accelerator and Fusion Research Division $120,000 47 Controlled Combustion

University of California 06-C A.K Oppenheim

Berkeley, CA 94720 87-3

The principal objective of this study is to provide

46. Studies in Nonlinear Dynamics scientific background for the development of controlA.N. Kaufman, R.G. Littlejohn led combustion systems, i.e. prime movers whose

combustors are not only sources of power, as they are

This project involves studies of fundamental proper- today, but operate also as modern, high-tech chemities of nonlinear dynamical systems which arise in cal reactors, so that the evolution of exothermic enerphysical situation of importance to energy research. gy is carried out under proper fluid mechanical and

A major area of theoretical investigation concerns thermo-chemical conditions to eliminate all sorts of

several different aspects of wave systems. Special combustion instabilities and minimize the formation

focus is given to wave packets; the role played by the of pollutants. For automobile engines this offers the

Maslov index in multidimensional wave problems; the prospect of efficient and clean combustion associated

occurrence of Berry's phase in wave and other with relatively low exhaust temperature, devoid of the

dynamical systems; the role of periodic orbits in the problems of knock and cycle-to-cycle variation, leadspectrum of chaotic wave systems; and linear mode ing thus to the annihilation of major technological

conversion. Recent progress includes the exploration constraints imposed upon the automotive industry:

of the relation between the Maslov index and the the octane standard and the catalytic converter.

phase space structures of nonlinear Hamiltonian Means to accomplish this involve the exploitation of

dynamical systems; new methods of computing the active radicals obtainable from plasma and flame jets

Maslov index, both for finding wave functions and as well as from recirculated products. Major

eigenvalues; elucidation of the relationship between laboratory apparatus for our studies consists of a

the Bohr-Sommerfeld and Maslov phases and the shock tube and molecular beam mass spectrometer,

recently discovered "Berry's phase"; a discovery of associated with an assortment of laser-powered optiBerry's phase in the adiabatic motion of charged par- cal instuments, including apparatus for megacycleticles in magnetic fields; a study of complex rays in frequency schlieren cinematography and laser

eikonal theory, and their relation to complex Lagran- induced fluorescence imagery. The experimental

gian manifolds, Stokes' lines and turning points; a program is associated with a significant effort in

numerical exploration of the role of periodic orbits in numerical modeling of the fluid mechanical, therthe spectrum of a chaotic wave system; and the first modynamic, and chemical kinetic processes influenctreatment of mode conversion phenomena for multi- ing the control of ignition and combustion in

dimensional systems, involving novel "reduction" engineers.

techniques. Emphasis is given to the use of a phase

space approach to wave phenomena in all these applications. A second area of investigation concerns

action principles, which are being used to imbed

single-particle Lie transform perturbation methods in

collective models, such as Vlasov-Maxwell systems.

Nonlinear phenomena (e.g., ponderomotive forces)

are thus dealt with systematically.

Engineering Research 21 1988
LOS ALAMOS NATIONAL UNIVERSITY OF MARYLAND

LABORATORY Department of Mechanical Engineering $78,000

Theoretical Division $90,000 College Park, MD 20742 01-C

Los Alamos, NM 87545 01-C 87-2

87-3

49. The Use of Optical Flow Fields in

48. Lattice Gas Hydrodynamics: Theory and Establishing Stereo Correspondence

Simulations J.H. Duncan

B. Hasslacher, U. Frish, Y Pomeau

The major difficulty in the analysis of stereo images is

Lattice gases, operating as cellular automata and establishing correspondence, ie., finding features in

amendable to massive parallelishm, which simulate one image that correspond to given features in the

the Navier-Stokes equation in two and three dimen- other image. For static stero pairs, a number of

sions, were introduced in 1985 by the prinicpal inves- methods have been developed to establish correspontigators (Phys. Rev. Lett.). Such lattice gases are dence. These methods are time consuming and difformed of "Boolean molecules" with discrete time, ficult to implement at the edges of ojects where the

space, and velocity. Their collision laws are designed range is discontinuous. In many applications, there is

to conserve particle number and momentum. Macro- relative motion between the camera pair and the obscopic momentum averages satisfy the incompres- jects in the field of view. In these cases, it is possible

sible Navier-Stokes equation, in a suitable physical to obtain an optical flow field in the left and right imlimit. Groups in the United States and in France are ages. Since the relative motion between the cameras

already engaged in theory, simulations, and hardware is known, equations can be derived relating the left

projects for lattice gas hydrodynamics. Preliminary and right image flow fields. One relation is obtained

results indicate that the method is easy to implement by subtracting the flow fields; the resulting equation

(with or without boundaries), robust, and for the rate of change of disparity is called the

reproducers known hydrodynamic phenomena. It binocular flow equation. Preliminary calculations

may eventually yield a new simulation strategy for and experimetns for rigidly attached, parallel cameracomplex turbulent flows, with many practical applica- pari configurations have shown that this relation is

tions. promising as a guid for establishing correspondence:

potential matches can be tested by sustituting the

It was proposed that the lattice gas method be measured positions and velocities of the features into

evaluated, and that modified models with higher the equation. In the present study, the binocular flow

Reynolds numbers be studied. Two-dimensional equation is being exp.ored in detail to find the limits

computer models were created to run on the CRAY- of its usefulness in establishing correspondence in

XMP, the CRAY II, and on the Connection Machine terms of camera- pair motions and surface shapes.

II (a computer with 65,000 central processors). These

models ran at the rate of 80,000,000, 10,000,000, and

2,000,000,000 cell updates per second, respectively.

Comparisons withother calculational methods have UNIVERSITY OF MARYLAND

been done. A three-dimensional program has been Department of Electrical Engineering $68,000

developed which produced the highest Reynolds College Park, MD 20742 06-C

numbers attainable with 24 bits required per cell. 83

Flow past a square plate has been successfully

modeled by this code. Summaries of this and other 50. Study of Magnetostatic Problems in

recent work has been published in several articles in Nonlinear Media with Hysteresis

the August issue of Complex Systems. Lattice gas I.C. Mayergoyz

methods for solving partial differential equations appear useful and promising. Expectations of their This project has two main research objectives: (1) to

capabilities on future machines are now being es- develop boundary Galerkin's approach and its

timated. quasifiniteelement realization in order to circumvent

the difficulties which are related to the unbounded

regions of field distribution, and (2) to investigate

mathematical models of hysteresis and develop the

Engineering Research 22 1988
methods for the calculation of magnetostatic Further, we are also interested in the synthesis of wrist

problems in media with hysteresis. mechanisms with a redundant DOF. Clearly, wrist

with redundant degrees of freedom can be used to As far as the first objective is concerned, the calcula- w r d

tion magnetic of fields in unbounded regions wn be avoid the singularity problem and to increase the dex- tion of magnetic fields in unbounded regions will be

reduced to coupled boundary/volume Galerkin's te ofa obot

forms and a new quasifiniteelement projection tech- For the reason of simplicity, most of the robot arms

nique will be developed on this basis. The problems have been designed in an open-loop configuration

concerning convergence of the quasifiniteelement which requires the actuators to be mounted on the

methods, existence and uniqueness of the solution of moving links. Robot arms using gear trains for power

simultaneous nonlinear quasi- finiteelement equa- transmission, can be configured with most of its actions and global iterative methods of the calculation tuators ground-connected which has the advantage of

of the solution of these equations will be the focus of reduced inertia. We believe this is a new concept in

this research. robot design. We will be exploring the design of such

robot arms from kinematic, dynamic and control For the second objective, mathematical models of ntfvi

hysteresis as continuous superposition of rectangular

hysteresis nonlinearities will be investigated. Special

attention will be paid to the solution of identification

problems and to the generalization of these models UNIVERSITY OF MARYLAND

for the case of vector hysteresis. The application of Department of Mechanical Engineering $125,000

continuation methods to the calculation of magnetos- College Park, MD 20742 01-C

tatic fields in media with hysteresis will be studied. 87-3

52. Comparative Study of the Vorticity Field in

UNIVERSITY OF MARYLAND Turbulent Flows: Theory, Experiment,

Department of Mechanical Engineering $88,000 Computations

and Systems Research Center 03-A J.M. Wallace

College Park, MD 20742 88-3

This is a collaborative project with the City College of

S 1. Ie Creation of Multi-Degree-of Freedom New York and the University of Houston. Fun- 51. The Creation of Multi-Degrce-of-Freedom 5.TMechanisms for M Robof Ap-fions atc ddamental studies of the vorticity field in a number of

haniss fr R ic A icatis standard sheared and unsheared turbulent flows are

being carried out. The research involves theoretical,

computational and experimental investigations. This research is concerned with one of the most dif-tional and experimental investigations.

ficult stages of mechanical design, namely the crea- Theoretically, a mathematically derivation of a definition of mechanisms. The objective of this work is to tion of 3-dimensional coherent structures superimdevelop a methodology for the creation of multi-DOF posed on chaotic motion is being developed with an

(Degree-Of-Freedom) epicyclic-gear-trains and to algorithm to educt these structures. The topological

apply these gear trains for the design of robotic complexity of the vorticity field and its relation to the

devices. In order to ensure all the potential epicyclic- basic processes of spectral energy transfer, vorticity

gear-trains be systematically identified, it will be generation and intermittency will be mathematically

necessary to develop computational algorithms, described in physical space.

based on graph theory and combinatorial analysis, for based on raph theory and combatorial. analysi, for Numerically a full Navier- Stokes simulation code of the enumeration of such mecbanisms. The creation

of multi-DOF mechanims will not provide only an the turbulent round jet as well as a high resolution of multi-DOF mechanisms will not only provide an code for box turbulence with periodic boundary conatlas for practicing engineering but also lead to more od o lece with peiodic od co

efficient design of these mechanisms with multiple ac- ditio n s s beng developed. With these codes the

tuating requirements. coherent structures definitions described above will

be applied and a detailed study of energy transfer and

The structural characteristics associated with the helicity fluxes will be conducted.

design of wrist mechanism has been investigated. We ri t t iri

have found that most of the robot wrists are made up Expementally che University of Maryland Turof a true two-DOF epicyclic-gear-train in series with b u l e n c e R e s ea r c h Laboratory ne-sensor hot-wire

the base link. We believe a class of new and novel probe for simultaneously sensing the instantaneous the be.eve base link. a class We ovelocity and vorticity vector fields in turbulent flows robotic wrists can be synthesized in a similar manner.

Engineering Research 23 1988
will be further developed. Point measurements will be UNIVERSITY OF MASSACHUSETTS

made in a variety of high quality flows (grid flow, jets, Chemical Engineering Department $120,000

mixing layers, wakes, boundary layers) in order to ob- Goessmann Laboratory 03-A

tain properties of the vorticity and helicity fields. Amherst, MA 01003-0011 83-6

From this data set, flow gradient quantities (helicity,

enstrophy, vorticity, strain-rate) associated with

coherent structures in these flows will be educted. 54. Screening Alternative Control Structures for

This experimental part of the project is being carried Plant Control System

out by the Universities of Maryland and Houston in a J.M. Douglas, M.F. Malone

cooperative effort.

An interactive computer code that helps the user to

develop a conceptual design of a petrochemical

UNIVERSITY OF MASSACHUSETTS process has been completed, and a similar code that

helps the user to retrofit a process is about 75% comChemical Engineering Department $ 91,000 plete. A code that estimates the incremental costs asAmherst, MA 01003-0011 06A sociated with the steady state control of the process is

88-3 currently being developed. That is, the code helps to

identify the dominant distrubances, it checks to see if

53. Design and Synthesis of Reactive Separation an adequate number of manipulative variables are

Systems available for control (and it calculates the costs asM.F. Doherty sociated with modifying the flowsheet to ensure that

the process is controllable), it assess if equipment

The design and synthesis of chemical process flow- constraints are encountered when disturbances enter

sheets usually begins by breaking the problem down the process and manipulative variables are changed

into three main sub-tasks. These are: synthesis of the to compensate for these disturbances (and it esreactor system, synthesis of the separation system and timates the costs required to remove these conthe development of an energy management system straints), and it suggests control system alternatives

(i.e. heat integration). Although these tasks are not that give close to the optimum operating costs.

independent of each other, such a decomposition has We are also building dynamic models of complete

the advantage of making a very difficult problem more processes in order to determine the effect of control

manageable. The second stage of such a procedure system alternatives on the total operating costs of the

then corrects for mismatches between the sub-tasks. complete process. We intend to use the results of

The above view of flowsheet synthesis can be radical- these studies to develop short-cut procedures for

ly altered when the reactions occur in the liquid phase. screening control system alternatives. Some short-cut

In such circumstances, it is often possible to combine models have been developed, but these need to be

the reaction and separation tasks by using reactive tested against rigorous simulations.

separators. Fundamental studies on the phase behavior, design and synthesis of this class of problems

are proposed. It is expected that this will lead to a sys- UNIVERSITY OF MASSACHUSETTS

tematic technique for inventing improved technology Chemical Engineering Department $55,000

and that this will be of lasting value to the profession. Goessmann Laboratory 06-C

Amherst, MA 01003-0011 88-3

55. Mixing of Viscous Fluids: Behavior of

Microstructures and Chaos

J.M. Ottino

In spite of its universality and practical implications,

the understanding of the fundamentals of mixing

remains rather incomplete. This work focuses on

basic experimental and computational studies along

two main themes with the objective of establishing a

framework capable of addressing mixing problems

encountered in nature and technology: (1) investigaEngineering Research 24 1988
tions of chaotic mixing of single fluids in determinis- teristics is planned. The development of a pdf

tic two- and three-dimensional flows, and (2) description of the turbulent flame behavior follows

dynamics of microstructures in such flows (e.g., the experiment closely. The approach is to model the

stretching, breakup, coagulation, etc.). Work in area topology of the flame surface by studying their

(1) is underway and a clear picture is emerging (for a kinematics and dynamics. Initially the reaction zone

general presentation of experimental and computa- will be modelled as a simple regular propagating surtional studies see J.M. Ottino, C.W. Leong, H. Rising, face which propagates at the laminar flame speed.

and P.D. Swanson, Morphological structures Then the effects of curvature and stretching on the

produced by mixing in chaotic flows, Nature, 333,419- flame speed will be added and local breakdown on the

425, 1988). Experimental work is planned to address regular surface due to self-intersection and the formathe problems listed under area (2). However, most of tion of cusps will be examined. The experimental and

the results to-date are due to simulation; a computa- theoretical efforts will lead to a comprehensive

tional study focused on coagulation of point particles description of the turbulent premixed flames.

in chaotic flows. The particles are convected without

diffusion and allowed to coagulate with probability

one when their mutual distance is less than d. The MASSACHUSETTS INSTITUTE OF

most significant finding is that under "well mixed" con- TECHNOLOGY

ditions the system behaves as if the particles were T

moved by Brownian motion and a simple kinetic The EnergLaborato $127,000

model describes the main results. The poorly mixed Cambridge, MA 02139 03-B

case is considerably more complex. In this case spatial inhomogeneities result from competition between

the rate of coagulation and mixing, and trapping and 57. Metal Transfer in Gas Metal Arc Welding

leaking of clusters due to KAM surfaces (FJ. Muzzio T.W. Eagar

and J.M. Ottino, Coagulation in chaotic flows, Phys.

Rev. A, 38, to appear Sept. 1988). Studies continue in The present research is part of a cooperative program

this area. among faculty at MIT and staff at Idaho National Engineering Laboratory to develop sensing and control

methods which can be used to automate the gas metal

MASSACHUSETTS INSTITUTE OF arc welding processes.

TECHNOLOGY Current research emphasizes understanding of the

The Energy Laboratory $135,000 forces controlling droplet detachment in gas metal arc

Cambridge, MA 02139 06-B welding. Experimentally, a laser back lit viewing sys86-3 ter has been developed which permits viewing of

anode and cathode jet phenomena. Welds have been

56. Turbulent Premixed Flame Study made with a variety of different metals (steel, 56. Turbulent Premixed Flame Study WU Cheng, . Keck S. Pope aluminum and titanium) in different shielding gases (Corm~ell University)' (argon, helium, carbon dioxide). It is seen that the

anode spot behavior changes dramatically with chan-

-,,.* . . .. . . ~ . ~ ges ~ in both metal and gas composition. This program is a combined experimental and

theoretical study of premixed turbulent flames. The This experimental information is being coupled with

primary aim of the experiment is to study the growth a model of the forces controlling metal transfer.

behavior and some detailed properties of statistically These include gravitation, surface tension,

spherical flames. The theoretical part of the program aerodynamic drag, electromagnetic (Lorentz) force

centers on the description of the flame behavior using and plasma jet momentum. Initial studies show that

the pdf formulation. Techniques using a thin sheet globular transfer can be described quantitatively by

laser light to illuminate the flame ball have been previous theories which were presented originally in

developed to look at the relationship between the only a qualitative manner. Quantification of previous

flame structure and the burn rate. The illuminated explanations of spray transfer depart markedly from

flow will be recorded on high speed movies and the the experimental observations. A new model of the

image will be digitized. Then the topology and globular to spray transition has been hypothesized

dynamics of the flame structures will be analyzed and is currently being studied with a finite element

statistically. Experiments to examine the effect of model.

pressure gradient on the flame propagation characEngineering Research 25 1988
It is believed that this work will ultimately be useful in MASSACHUSETTS INSTITUTE OF

understanding metal transfer in pulsed current gas TECHNOLOGY

metal arc welding. This study also interfaces with the Department of Materials Science $71,000

experimental and theoretical gas metal arc welding and Engineering 06A

control models being developed at MIT by Professor Cambridge, MA 02139 85-4

D. Hardt and at INEL.

59. Plasma Reduction of Metallic Oxides

MASSACHUSETTS INSTITUTE OF JF Elliot J. Sekely

TECHNOLOGY The objective of this research is the characterization

Department of Materials Science of reactions in composite carbon-metal oxide parand Engineering $125,000 tides and the possible reduction of metal oxide parCambridge, MA 02139 06-A ties injected into the tail flame of a thermal arc

88-3 plasma. The experimental program consists of injecting particles in the size range of 5 to 50 microns into

58. High Temperature Gas-Particle Reactions the plasma flame, and then extracting these particles

J.F. Elliot P.P. Bolsaitis with a quenching tool at various positions down

stream from the injection point. The collected parThe purpose of the research is to examine the physico- tides are examined by optical and electron microschemical behavior of individual organic particles for copy to obtain information on the changes such as

conditions simulating those to which particles are ex- melting, evaporation, reduction, etc., that occur

posed during thermal plasma processing methods, during the transit of the particles in the flame.

The particle is suspended in a closed chamber by an Samples of powders with a very small size range will

electrostatic field, and it is heated by a pulsed laser be employed in studies of evaporation and melting.

beam. The composition of the gas in the reactor can The temperature and velocity fields of the plasma

be controlled, and the temperature of the particle can flame are being calculated with a computer program

be measured with a time resolution as short as one or that has been developed for that purpose. The rate of

two milliseconds. Equipment is being installed forop- heat transfer from the flame to the particles will be

tical imaging of the particle during processing. determined in experiments in which particles with difStudy is in progress of melting and solidification of ferent, but always well characterized, thermo-physimetal and oxide particles at high rates of heating and cal properties are employed. By sectioning and

cooling. Measurements have been made of the analyzing these particles, it is possible to determine

evaporation of oxide particles while they are heated the extent of melting, and of vaporization that has ocand cooled. Investigation of the ignition and combus- curred. The results will be compared with predictions

tion of metal particles is in progress also. Means have by use of the computer model.

been developed for capturing individual particles and The work is closely coordinated with plasma modellexamining them by optical and electron microscopic ing and gas-particle studies at MIT, and with

methods. measurements of particle trajectories and temperaThis work is closely connected with the experimental tures of plasma flames that are in progress at the

program on plasma processing at the Idaho National Idaho National Engineering Laboratory.

Engineering Laboratory, and other plasma processing studies in the Department of Materials Science

and Engineering at MIT.

Engineering Research 26 1988
MASSACHUSETTS INSTITUTE OF MASSACHUSETTS INSTITUTE OF

TECHNOLOGY TECHNOLOGY

Energy Laboratory $103,000 Energy Laboratory $175,000

Cambridge, MA 02139 03-A Cambridge, MA 02139 06-C

88-3 88-3

60. Synthesis of Heat and Work Integration 61. A Parity Simulator for Nuclear Power Plant

Systems for Chemical Process Plants Dymanics

L.B. Evans KF. Hansen

The goal of this research is to investigate and develop The simulation of the behavior of dynamic systems is

improved methodologies for the synthesis of heat and an important part of the computer field. The great

work integration systems in process plants. This is an advances in digital electronics are such that most

important problem in the design of new plants and in simulation is done digitally. However, problems unithe retrofitting of existing plants for energy conserva- que to the use of digital computers, such as computer

tion. languages, numerical algorithms, and computer/user

In a typil s p , sh as a p m interfaces have made simulation of engineering sys- In a typical process plant, such as a petroleum tes dfficulat and/or awkward. This is particularly

refinery, a petrochemical plant, or a paper mil~ many process saetreams must be heated or cooled in heat yx- true with regard to transient analysis of nuclear power process streams must be heated or cooled in heat exchangers. The heat integration system recovers heat ants

from streams that must be cooled and transfers it to One area of analog simulation that has remained in

streams that must be heated. A plant also requires widespread use is that of "breadboard" circuits to

energy in the form of work to drive pumps and cor- simulate electronic networks. Recent developments

pressors and to provide mechanical energy needed. have led to a very flexible and convenient breadboard

This work must be supplied externally, such as by pur- technique called parity simulation, where individual

chasing electricity from a utility, or generated inter- integrated circuits in the simulator behave as innally within the plant. The goal of work integration is dividual circuit elements. The system is also user

to identify process modifications that can reduce the friendly in that the analyst communicates in his own

cost of energy in the form of both heat and work. engineering language. It is well-known that electric

analogs can be constructed to other physical systems This project aims to combine powerful mathematical analg can e cntructed

programming techniques with principles of artificial such as mechancal thermal fluid magnetic or

intelligence and include improved energy integration acoustic systems

methodologies so as to develop a user-friendly The research objective of this project is to study the

prototype system for heat and work integration in applicability of the parity simulation concept to fluidprocess plants. With this objective in mind, fun- flow systems such as encountered in nuclear power

damental research is being conducted so as to under- plants. Work to date has led to the successful

stand the important parameters involved and their electronic modelling of plant componens such as

interactions. Algorithms and heuristics are being pumps, pipes, reactor cores, heat exchangers, etc. The

developed to synthesize that heat and work integra- IC elements constructed have been used to solve the

tion system having minimum total cost. conservation of mass, energy, and momentum in

single-phase incompressible and compressible flow, The net result of this research will be improved un- sile-phase incompressible and compressible ow

as well as two-phase homogeneous equilibrium flow. derstanding of the nature of the problem of energy in- as wel as two-phase homogeneous equilibrium

tegration in process plants. The prototype system

being developed will help engineers solve realistic industrial problems.

Engineering Research 27 1988
MASSACHUSETTS INSTITUTE OF MASSACHUSETTS INSTITUTE OF

TECHNOLOGY TECHNOLOGY

Laboratory for Manufacturing $156,000 Department of Mechanical Engineering $68,000

and Productivity 03-B Cambridge, MA 02139 01-D

Cambridge, Massachusetts 02139 88-3 87-2

62. Multivariable Control Of The Gas-Metal Arc 63. The Development of a Friction Model

Welding Process Predicting the Sliding Behavior of Material

D.E. Hardt Pairs, Especially at Low Temperatures

Y. Iwasa

Gas Metal Arc Welding (GMAW) is a complex

process involving thermal, geometric, and metallurgi- The principal objectives of this research program are

cal transformations. Our work has been addressing 1) to develop a friction model which predicts correctthe use of multivariable control methods to develop a ly whether a system sliding at low speeds will give

comprehensive process control methodology for this steady or unsteady sliding behavior and 2) to advance

and potentially other fusion welding processes. We basic understanding of the friction process.

have so far progressed on two independent fronts:

easurement and control of geoetric properties of The program consists of experimental and analytical measurement and control of geometric properties of

the weld and measurement and control of weldment studies. Expermental work incudes collection of poeresd teaurema van h . r control o data on creep properties of the two contacting properties via thermal history control. materials, namely bulk creep behavior in tension and

For the latter we have analyzed the process to develop interface creep data in shear. The interface creep

a 3 input -3 output process model. The inputs include takes place when one material is pressed against the

arc power, arc speed and high frequency arc motion other by a constant force and a shear force insufficient

(used to distribute the arc power along the weld line). to produce gross sliding is applied. The extent to

The outputs comprise heat affected zone width, which the bulk creep properties determine the intercenterline cooling rate and overall weld cross section- facial creep behavior both at room temperature and

al area. A full non-linear numerical simulation for at cryogenic temperatures will be determined, and

this process has been developed and equivalent non- this knowledge should lead to better models of the

stationary linear transfer functions were used to ex- friction process. In turn, such knowlege will conplore the real-time control problem based on surface tribute to a more reliable operation of superconducttemperature measurement. It was found that because ing magnets.

of the vast parameter variations present in welding the

adaptive control methods are necessary for stable

regulation. An adaptive control to regulate two out- MASSACHUSETTS INSTITUTE OF

put variables (heat affected zone width and cooling TECHNOLOGY

rate) was implemented and used to successfully co- v a

demonstrate stable regulation of this non-linear, Department ofOceanEngineering $41,000

dynamically coupled system. Cambridge, MA 02139 03

85-4

As for geometry control, we have concentrated on

both bead contour measurement methods and on

control models for the process. Off-line measure- 64. In-Process Control of Residual Stresses and

ments using a standard structured light approach DistortioninAutomaticWelding

have been made, but these have proven to be insufi- K Masubuchi

cient for high bandwidth real-time control. Accordingly we have begun development of a enhanced The objective of this research is to develop the techsystem based on strobe light and gated CCD camera nology of i-process control of residual stresses and

technology. Using these sensing system we have iden- distortion in automatic welding. The program contified transfer function relating bead width and rein- sists of the following phases:

forcement height to process inputs of wire feed rate Phase 1: In-process control of residual stresses and

and torch speed. These functions have as well proven distortion in some weldments.

to be non-stationary and control approaches will

again require adaptive methods. Phase 2: Development of technologies for minimizing and eliminating, if possible, tack welds.

Engineering Research 28 1988
Phase 2-1: Analytical and experimental studies of material strain hardening, load magnitude, and crack

thermal stresses during welding and forces acting on geometry. When such single-parameter dominance is

tack welds. obtained, correlations of crack response with J-inPhase 2-2: GMAW process control to tegral or related measures may be justified. The

terference from tack welds. analysis requires detailed finite element computa- tions which are too costly for routine applications, so

Phase 3: Plans for further development of the tech- further development of simplified analytical models

nology of in-process control of residual stresses and such as the so-called "line-spring" model is underway.

~~~~~~~distortion. ~To date, detailed non-linear three-dimensional finite

Phase 2-2 has been added since July 1986. The re- element studies of surface cracks under predominant

search efforts thus far covered all phases but Phase 3, tension show that the asymptotic HRR stress fields of

which will be done at the end of the program. power law hardening materials typically dominate for

Te t m ur e r P e 1 hs bn to sy normal stress levels up to 75% of yield strength, with

The major effort under Phase 1 has been to study a rapid loss of dominance at higher load levels. Calmeans for reducing distortions and residual stresses deformations are in good agree- culated crack front deformations are in good agree- in girth-welded pipes. It has been found that an ap- ment with experimental measurements made at the

plication of internal pressures during welding is an ef- I o Ntion Engineering Laboratory. The line- . means of reuigIdaho National Engineering Laboratory. The linefective means of reducing radial distortion, spring has been generalized to include elastic/power

The major effort under Phase 2-1 has been to study law behavior, and resulting solutions are within a few

transient thermal stresses and metal movement percent of corresponding continuum solutions reduring butt welding of steel and aluminum plates. It quiring more than an order of magnitude more cornhas been found through experiments that forces ac- putation.

ting on tack welds can be significantly reduced by ad- Finally, detailed three-dimensional studies of

ditional heating by oxyacetylene torches placed through-cracks in "thin" sheets has accurately quanalongside alongside the welding arc. Through an analytical the welding arc. Through an analytical tilied the stress intensity variation through the thickstudy it has been found that the most effective way is ness, as well as the boudary layer structure near the to hea areas wide to.relativelylowtemperatureso ness, as well as the boundary layer structure near the to heat wide areas to relatively low temperatures so intersection of the crack front with the free surface. tha counter (a) the metal movement produced by the intersection of the crack front with the free surface. that (a) the counter metal movement produced by the

additional heating is significant, but (b) the supplementary heating does not produce additional

residual stresses. MASSACUSETTS INSTITUTE OF

TECHNOLOGY Under Phase 2-2, basic research has been conducted TECHNOLOGY

on possible ways for minimizing interference of tack e Energy Laboratory $130,000

welds by increasing penetration of the main root-pass Cambridge, MA 02139 01-A

welding.

66. Energetics of Comminution

MASSACHUSETTS INSTITUTE OF c. Peterson

TECHNOLOGY

prtment of En Mechanical g This program is central to a broader program of comDepartment of Mechanical Engineering $192,000 minution research that includes basic studies on the

Cambridge, MA 02139 01-3 behavior of single particles, particulate beds, and the

design and testing of a novel coal crushing concept.

65. Modeling and Analysis Of Surface Crack Single particle work has progressed the furthest. A

5. Moln an Analysis of urface Cr a cks very rigid miniature compression testing device has

been fabricated and data generation has just begun.

Behavior of the device is satisfactory and computer This research focuses on the analysis of ductile crack data acquisition is being installed to permit routine

initiation, growth and instability in part-through sur- testing of a statistically significant number of particles.

face-cracked plates and shells. The overall approach This device will provide information on force and

consists of determining parametric limits of ap- requirements for particle fracture as a funcplicability of the "dominant singularity" formalism ofre s particle fracture a f n

nonlinear fracture mechanics in these crack con- t of sie artice an materia proposed which

figurations as they are influenced (principally) by theory of co on has been proposed which

Engineering Research 29 1988
seems to explain the shift in energies required for MASSACHUSETTS INSTITUTE OF

failure as size decreases for uniform materials. More TECHNOLOGY 1

complex materials such as particles with voids and Department of Chemical Engineering $54,000

composite materials will be examined next. The in- Cambridge, MA 0239 06-C

creased difficulty to fracture a particle of smaller size 88-3

has a practical significance in the crushing behavior

of particulate beds.

Particulated bed work will include both analytical and LOS ALAMOS NATIONAL

experimental studies, seeking the combination of bed LABORATORY 2

stress and strain required to cause individual particle $25000

fracture within some zones of the bed. These studies Design Engineerig D87545 0 ...,,.Los Alamos, NM 87545 06-C will ultimately tie back to the individual particle 88L

failure studies when computer simulations are used to

predict particle movements and forces acting on the

particles. ~particles. .SANDIA NATIONAL LABORATORIES3

A novel comminution mill has been designed which Fluid and Thermal Sciences Department $25,000

uses particle-to-particle shear to cause particle Albuquerque, NM 87185 06-C

failure. 88-3

MASSACUSETTS INSTITUTE OF 68. Macrostatistical Hydrodynamics TE CHNOLOGY INSTITUTE ~~vH. OF Brenner, A.K Grahanm, TECHNOLOGY L-A. Mondy3

Department of Materials Science $ 95,000

and Engineering 06-A This research aims to establish a link between a statisCambridge, MA 02139 88-3 tical knowledge of the microstructure and the macroscopic behavior of dispersed systems, such as

67. Mathematical Modelling of Transport suspensions of particles in liquids. Because current

Phenomena in Plasma Studies capability for predicting behavior of multiphase sysJ. Szekey tems is limited, this fundamental knowledge of

suspensions will benefit a host of technologies, espeThe purpose of this investigation is to develop a com- cially related to geothermal energy production,

prehensive mathematical representation of the petroleum production and refining, and synfuels

velocity field and of the temperature field in thermal processing. Currently empirical design procedures in

plasma systems and to compare the theoretical these technologies are deficient in understanding how

predictions with experimental measurements. overall system behavior is related to the system's

micromechanics.

The problem has been formulated through the statement of the axi-symmetric Navier-Stokes equations Our approach to enhancing this understanding involand the associated differential thermal energy and ves a novel combination of experiments, numerical

mass conservation relationships. The theoretical calculations, and theory. Real-time radiography,

predictions for the gas temperature profiles were high-speed video, and image processing are being

found to be in excellent agreement with the ex- used to observe and record the motions of balls as they

perimental measurements obtained by Dr. C. Shaw settle through suspensions of neutrally-buoyant parand Dr. J. Batdorf of the Idaho National Engineering tides. Measurements of the average and higher moLaboratory. The work is continuing with the objec- ments of the position and velocity distributions of the

tive of modelling gas mixing and representing the in- falling ball will provide boundary conditions for comteraction between the plasma gas and solid particles. puter simulations of the flow fields in the continuous

phase surrounding individual particles. This statistical knowledge of the microscale mechanical response

will enable development and verification of a new

theory for predicting overall macroscale mechanical

response of multiphase systems.

Engineering Research 30 1988
To date, experimental measurements of the three- UNIVERSITY OF MINNESOTA

dimensional position versus time of balls settling in Department of Aerospace Engineering $ 70,000

quiescent suspensions have been made, varying the and Mechanics 01-C

relative sizes of the ball and suspended spheres. A Minneapolis, MN 55455 87-3

theory has been developed to relate the average ball

velocity to the macroscopic suspension viscosity.

Finally, various test problems have been performed to 70. Lubricated Pipelining

establish the appropriate boundary conditions for D.D. Joseph

both finite-element and boundary-element models of

suspensions. This project has as its aim the understanding and control of water lubricated pipelining of viscous crude

oils, coal-oil dispersions and other viscous materials.

i~UNIVERSITY OF MINNESO~TA ~ The basis for this work is that there are domains of

DUNIVERSITY MechanicalEngineeringparameters OF MINNESOTA in which water lubricated transportation Department of Mechanical Engineering $116,000 of viscous materials is stable. The lubricated conMinneapolis, MN 55455 01-B figurations can introduce enormous savings of energy

874 in the form of reduced pressure gradients for enhanced transport. The studies underway are theoreti69. The Impact of Separated Flow on Heat and cal and experimental. The experimental studies are

Mass Transfer on the transportation of coal oil dispersions, on the

RJ. Goldstein properties of emulsified solutions at large shear, and

on stable wavy interfaces arising from nonlinear interIn many real flow systems separation occurs either in- actions. The problem of coal-oil dispersions is to

tentionally or unintentially. Such separations, often know if the coal can be made to stay in the oil under

unsteady by nature, tend to result in three-dimen- conditions of lubricated transport. Stability calculasional and secondary flows. Heat and mass transfer tions underway are designed to identify the windows

in some situations can be unsteady, there can be ener- of parameters in which core annular flow is stable and

gy separation in the flow and often large gradients in to calculate maximum growth rates for unstable flow.

heat and/or mass transfer occur which are difficult to Future studies will concentrate on extensions to inmeasure. The proposed study will include a variety of elude effects of oil wetted walls, gravity and nonlinear

flow situations involving separation and also the mechanisms.

development of special measurement techniques to

study the heat and mass transfer in the presence of

large gradients. Situations to be studied include the UNIVERSITY OF MINNESOTA

flow over two and three-dimensional steps, separation Department of Mechanical Engineering $361,000

of the flow around circular and square cylinders Minneapolis, MN 55455 06-C

projecting from surfaces including the influence of a 88-3

horseshoe vortex and localized fins, flow through a

porous medium represented by a simple flow, and the

vortex rings formed around a jet as it flows out of an 71. Thermal Plasma Processing of Materials

orifice or nozzle. These include the development of E. Pfender

precision microsensors for highly localized measurements of the heat flux, and further development of The objective of this research project has been a comtechniques for local mass transfer measurement. bined experimental and analytical study for thermal

plasma processing of materials including the production of fine ceramic powders.

For the experimental work, a new Triple Torch Plasma Reactor with three identical DC torches has been

developed for plasma processing of materials. This

new reactor offers enhanced flexibility in terms of

torch orientation and increased power levels.

Fine ceramic powders have been successfully synthesized in a previously developed DC plasma jet

reactor using a novel liquid injection method.

Engineering Research 31 1988
Aqueous solutions of inorganic metal salts have been A shearing cell for less viscous and aqueous solutions

used as the precursors to synthesize single phase or is under construction and scattering data will be taken

composite oxides such as the high Tc superconduct- in the near future. Candidate solutions are suspening oxide. In the synthesis of single phase carbides sions and solutions of biological interest.

such as SiC, non-aqueous organometallic solutions of

a single metal component are used as precursors.

Vortex or swirl gas flows are frequently employed in NATIONAL INSTITUTE OF

plasma systems such as DC plasma torches for arc STANDARDS AND TECHNOLOGY

stabilization. A two-dimensional model for turbulent Chemical Engineering Science Division $109,000

plasma jets with superimposed vortex flow has been Center for Chemical Engineering 01-C

developed, incorporating multiple time scales for Boulder, CO 80303-3328 87-2

velocity and temperature fluctuations, and a densityweighted averaging for the density fluctuation effect.

Comparisons of theoretical predictions based on the 73- Residence Time Distribution Approach to the

present model with available experimental data are, Study of Free Convection in Porous Media

in general, in reasonable agreement. M. Jones, R Perkins, . Wolfe

The structure and dynamics of the global flow patNATIONAL INSToITUTE OF terns of free-convective flows in confined porous NATIONAL INSTITUTE O*F media is an important area of study form many enSTANDARDS AND TECHNOLOGY gineering applications. In this project, a new exThermophysics Division $87,000 perimental approach is being developed based on the

Boulder, CO 80303 06-A principles of residence time distributions. Earlier

87-2 work has shown these to be a sensitive indicator of

such flow patterns.

72. Neutron Scattering From a Sheared Liquid: On the experimental side, a new laser fluorescence

a Proposal to Construct the Shearing fiberoptic probe of superior sensitivity has been sucApparatus cessfully developed. Arrays of such probes are being

HJ.M. Hanley used with fluorescent dyes to detect flow patterns in

fluid-saturated containers filled with uniform glass

The project aims at the development of equipment to spheres subject to free-convective flows under

measure the microstructure of liquids out of equi- precisely controlled conditions. In order to interpret

librium. The objective of the research is to inves- the experimental results, a computer code is under

tigate, via neutron scattering, liquids subjected to a development in which the progress of a tracer can be

shear. The work will focus on the examination of the followed in three dimensions for convecting patterns

variation of the structure with respect to a universal appropriate to a range of Rayleigh numbers and

parameter, the relaxation time. The relaxation time throughflow Peclet numbers. The role of non-linear

is the key to characterizing the complexity of the fluid drag and of non-isotropic dispersion for both heat and

(i.e., complex versus simple) and how it will behave mass tranport is being studied. Unsteady flows known

out of equilibrium. to exist at high Rayleigh numbers are of particular inA preliminary shearing cell has been completed and terest.

preliminary neutron scattering data from supercooled (viscosity = 108 Pa.s) D-glycerol taken. The

cell will be modified to investigate temperature

gradients and viscous heating in the sample. Neutron

scattering data will be remeasured. The structure of

the liquid will be inferred from the intensity patterns

when the fluid is at rest and when it is sheared. Of

particular interest is the possible structure that may

extend over several molecular diameters.

* Formerly the National Bureau of Standards

Engineering Research 32 1988
NATIONAL INSTITUTE OF THE CITY UNIVERSITY OF NEW YORK

STANDARDS AND TECHNOLOGY The City College

Thermophysics Division $120,000 The Benjamin Levich Institute $125,000

Boulder, CO 80303 03-B for Physico-Chemical Hydrodynamics 01-C

87-3 New York, New York 10031 87-3

74. Thermophysical Property Measurements in 75. Comparative Study of Vorticity Field in

Fluid Mixtures Turbulent Flows

NA. Olien, J.M.H. Sengers E. Levich

The project aims at the development of accurate The purpose of this project is to study - theoretically,

measurement capabilities for the thermophysical numerically, and experimentally coherence in vorproperties of complex, multiphase, fluid mixtures ticity field. During the last year the following results

containing hydrocarbons. The research is being done have been obtained.

jointly by two research groups within the Ther- jophtysis Divison oferhgoup NBS C the i rr Che. The analysis of the build up of coherence in numeri- mophysics Division of the NBS Center for Chemical

Engineering. One group is located at the cal isotropic turbulence has been performed. Large Engineering. One group is located at the Engitersbng. M l raoris a t oather. at the .. fluctuations of helicity and the growth of helicity at Gaithersburg, MD laboratories and the other at the Gaihersburg, MD laboratories. ad the other at the low scales been has detected in 128 x 128 x 128 simula- Boulder, CO laboratories. The properties involved tions of decay turbulence.

are PVT (pressure-volume- temperature), PVTx

(pressure-volume-composition), phase equilibria The comparative study of symmetry breaking in tur-

(liquid-vapor and liquid-liquid equilibria), phase be- bulence has been considered. It has been shown that

havior in interfaces, and transport properties (vis- in order to preserve statistical invariant the concosity, thermal conductivity, and diffusion tinuous growth of coupling H(k) H(k') is inevitable.

coefficient). The apparatus will be designed for use Laboratory experiments with two different systems -

in corrosive, highly corrosive, and sometimes toxic water past the grid and air past the grid -support this

and flammable fluids with measurements extending to observation. In both experiments helicity spectrum

high temperatures (800K) and high pressure (30 MPa has been measured and the build up of coherence was

and in some cases 70 MPa). Also under study are observed.

methods for evaluating supercritical solvent mixtures A t m

and related fluid mixtures. A theoretical model of the phase coherence in turbulence observed in numerical simulations of turThe most recently completed apparatus include a bulence and laboratory experiments has been

variable volume vapor-liquid equilibrium apparatus constructed. A stationary driven turbulence, was

for moderate temperature ranges; a Langmuir film reduced to a 4-D equilibrium system.

balance for use with aqueous, hydrocarbon, and

biopolymer systems; a magnetic suspension den- The study of the linear stability of incompressible tursimeter for high temperatures and pressures; a tor- bulent fluids with respect to coherent perturbations

sional crystal viscometer for high temperatures and which give a nonzero mean flow has been performed. sionalcrya f hs * r . a It was shown that there is no instability, in marked

pressures; and a transient hot-wire apparatus for ther- cntas sh o th at th e

ressible case, where te refe

mal conductivity measurements at high temperatures. conatast to the compressible case, where reflecThe latter two apparatus are capable ofreachingpres- t a of the basi turbulence rendered

sures near 70 MPa. certain helical perturbations unstable.

A method of creating initial field for simulations of

decaying turbulence has been developed which

enables creation of Gaussian velocity field with given

energy and helicity spectrum has been developed. It

has been shown in numerical experiments that strong

helicity slows down the cascade of energy and the buildup of enstrophy at all later times.

Engineering Research 33 1988
CITY UNIVERSITY OF NEW YORK reduce the study of complex physico-chemical sysThe City College t

e m s governed by strongly nonlinear, three-dimenDepartment of Chemical Engineering $80,000 sio n al and highly coupled sets of partial differential

New York, New York 10031 01-C equations to the incomparably more simple weakly

87-3 nonlinear evolution equations of lower space dimensions. These equations are then easily tractable either

analytically or numerically. With all their relative

76. Periodically Structured Multiphase Flows simplicity the reduced equations proved rich enough

and Hydrodynamic Instabilities in Narrow to capture many nontrivial features of physical sysChannels tems which hitherto resisted analytical description by

C.M. Maldarelli any other means. Specifically, in this study multiplescale methods are applied to the mathematical

The research to be undertaken in this project is con- modelling of curved nonsteady flames propagating in

cerned with understanding the hydrodynamics of the gaseous combustible mixtures. A nonlinear

flows of immiscible liquid phases in narrow capil- geometrically invariant dynamic equation for the

laries. The research has experimental and theoretical flame front evolution is derived on the assumption

components. The aim of the experimental com- that the curvature of the flame is small. The equation

ponent is to measure the pressure drops which are generalizes the corresponding weakly nonlinear

developed inthese flows, and the film thicnesses of the equation obtained previously near the stability

wetting layers deposited on the inside surface of the threshold. The new equation is capable of describing

capillary. The aim of the theoretical component is to the evolution of complex geometric flame configuradevelop a numerical algorithms to solve for the tions such as those frequently observed in a strongly

hydrodynamic flow, and to undertake a hydrodynaic turbulent gas flow.

stability analysis to describe the stability of the wetting

layer to the destabilizing effects of capillary and vis- A theory of chaotic, hexagonal and polyhedral spincosity stratification. ning flames is developed.

The major applications of theresearcharetothetech- Effects of acceleration on flame propagation in

nologies of enhanced oil recovery and lubicated horizontal, vertical and rotating channels are

pipelining. Each of these technologies involves the analyzed.

movement of immiscible phases. The results of our The concept of turbulent flame speed based on inexperimental and theoretical work should lead to the variant renormalization group approach is proposed.

identification of operating conditions for which the A consistent mathematical theory of premixed flame

multiphase flows are ordered. propagating in large-scale homogeneous turbulent

flow-field is elaborated. An equation for turbulent

flame speed as a function of the turbulent flow-field

CITY UNIVERSITY OF NEW YORK intensity is derived.

The City College The study is presently in progress of spontaneous forThe Benjamin Levich Institute $120,000 mation of large-scale structures in thin liquid films, in

of Physico-Chemical Hydrodynamics 06-C interfaces under directional solidification, and in visNew York, New York 10031 87-3 cous flows performingperiodicmotion at small scales.

77. Topics in Physico-Chemical Hydrodynamics

G.I. Sivashinsky

The objective of this project is a unified theoretical

approach to the description of large-scale spatio-temporal structures spontaneously emerging in a variety

of physico-chemical systems.

The significant difference between the characteristic

scales of the primary and secondary structures suggests the method of multiple scale asymptotic analysis

as a natural technique for solving the relevant mathematical problems. This approach enables one to

Engineering Research 34 1988
NORTH CAROLINA STATE NORTH CAROLINA STATE

UNIVERSITY UNIVERSITY

Department of Mechanical $67,000 Department of Mechanical $ 94,000

and Aerospace Engineering 06-B and Aerospace Engineering 06-A

Raleigh, NC 27695-7910 87-3 Raleigh, NC 27695-7910 86-3

78. Analysis of Transport Mechanisms in Dense 79. Transport Properties Of Disordered Porous

Fuel Droplet Sprays Media From The Microstructure

C. Kleinstreuer S. Torquato

Of interest are the effects of droplet interaction on the This research program is concerned with the quandroplet vaporization and heat transfer in spray sys- titative relationship between certain transport

tems. The dense spray portion is conceptualized as properties of a disordered porous medium that arise

two of three streamers of several closely spaced in various energy-related problems (e.g., thermal or

droplets in a non-isothermal environment. Two basic electrical conductivity and the fluid permeability) and

approaches are carried out to analyze and solve this its microstructure. In particular, we shall focus our

problem: (1) a finite element solution of the complete attention of studying the effect of: porosity, spatial

transport equations for thermal axisymmetric flow distribution of the phase elements, interfacial surface

past a linear array of solid spheres and vaporizing statistics, phase conductivity, and size distribution of

droplets at different spacings; and (2) a boundary- the phase elements, on the effective properties of

layer type solution at appropriately high Reynolds models of both unconsolidated media (e.g., soils and

numbers of single spheres/droplets with mixed con- packed beds of discrete particles) and consolidated

vection and wall mass transfer effects, and for several media (e.g., sandstones and sintered materials).

dynamically interacting, vaporizing droplets. dynam i acting, ly vaporing dopls. A theoretical formalism has been developed to repreThe direct integration of the coupled momentum, sent a general n-point distribution function from

heat and mass transfer equations for several closely- which one may compute any of the various types of

spaced spheres or droplets has been completed. The correlation functions that have arisen in the literature.

validated results in terms of drag/interaction coeffi- An efficient computer-simulation technique has also

cients and near-wake heat transfer parameters are been developed to obtain these statistical quantities.

being used in the approximate analysis of a single Employing such lower-order n-point distribution

streamer of several spheres/droplets. The boundary- functions, sharp bounds on the conductivity, elastic

layer study of mixed thermal convection past a sphere moduli, and permeability of models of porous media

with wall mass transfer and other effects has been have been computed. The rigorous bound on the percompleted. Some of the newly derived transforma- meability for random beds of spheres is relatively

tions from this fundamental research study will be close to the well-known Kozeny-Carman empirical

useful for the more elaborate investigation of several formula. Finally, the study of percolation of

interacting spheres/droplets. phenomena in continuum random-media models has

The fundamental analysis of multiple droplet systems recently begun.

is important for the physical understanding of dense

spray processes and for the improved design of fuel

droplet combustion as well as spray cooling, coating NORTHWESTERN UNIVERSITY

and absorption. Department of Civil Engineering $68,000

Evanston, IL 60208 03-B

86-3

80. Effects of Crack Geometry and Near-Crack

Material Behavior on Scattering of

Ultrasonic Waves for QNDE Applications

J.D. Achenbach

A crack in a solid body can, in principle, be detected

and characterized by its effect on an incident pulse of

ultrasonic wave motion.

Engineering Research 35 1988
The work on this project is concerned with applica- instabilities is given in which we include the effects of

tions of the scattered field approach to the detection viscosity, surface tension, thermocapillarity and van

and characterization of cracklike flaws. The work is der Waals forces.

both analytical and numerical in nature. Several for- i i i

ward to model slutions problems have proven to be In the latter case we examine experimentally the dimward solutions to model problems have proven to be pling of an oil film and compare quantitatively the invery helpful in the design of experimental configura- rfa rof m d anpve the

tions. They are also valuable in interpreting scatter- er f ae profies measued pedicted given the . ,t probletemperature .o the iverse profiles sensed with thermocouples. ing data for the inverse problem.

The efficacy of ultrasonic methods to detect and When the heated plate is tilted with respect to the

horizontal, a heated falling film is created. The characterize a crack depends on topographical fea- a . tures of the crack faces, the presence of in- former theory is generalized to examine the interplay

homogeneities in the crack's environment, and on the between the bul flow and evaporative eects

mechanical properties in the near-crack region. In

this work the effects on the scattered ultrasonic field

of various features of fatigue and stress corrosion NORTHWESTERN UNIVERSITY

cracks, such as partial crack closure, the presence of Department of Engineering Sciences $50,000

microcracks and microvoids, and near-tip zones of and Applied Mathematics 01-C

different mechanical properties have been inves- Evanston, Illinois 60208 88-3

tigated. Most of the results have been obtained by formulating a set of singular integral equations for the 2. Attenuation ofWaves in Partially Saturated

fields on the boundaries of the scattering obstacles. Porous Solids

These equations have been solved numerically by the MJ. Miksi

boundary element method, and the scattered fields

have subsequently been obtained by using repre- concerned with investigating the This project will be concerned with investigating the

sen als. tation int egr dissipation of energy associated with the motion of

For the configurations examined in this paper, crack fluid in a partially saturated material. An underclosure has the most significant effect on far-field standing of this process is important in explaining the

scattering. attenuation of waves (compressional and shear) in a

partially saturated porous material. It is also important in understanding how two immiscible fluids (e.g.

NORTHWESTERN UNIVERSITY oil and water) displace one another in a porous media.

Department of Engineering Sciences $111,000 On the microscopic scale we will allow the fluid to disand Applied Mathematics 01-B sipate energy by viscosity and by the movement of the

Evanston, IL 60208 863 contact line of the gas/liquid/solid intersection.

There are two parts of this project. The first concerns

an investigation of the fluid mechanics associated with

81. Thinning And Rupture of a Thin Liquid File contact line movement, while the second concerns

on a Horizontal Heated Solid Surface using these results in either existing or modifications

S.G. Bankoff, S.H. Davis of existing macroscopic theories of wave propagation

in a porous material.

A thin liquid film on a horizontal heated plate can become unstable and rupture exposing dry areas of the The first phase of this project is currently underway. come unstable and rupture exposing dry areas of the

,.plate.r A macroscopic theory of wave propagation in partially saturated porous media which includes the effects

For a volatile liquid we analyze the consequences of of contact line movement has been developed. There

evaporation on the layer, incorporating the effects of are several limitations on this model but it does show

viscosity, surface tension, vapor recoil, thermocapil- that there can be considerable error in attenuations if

larity and long-range molecular (van der Waals) for- contact line movement is neglected especially for low

ces in a nonlinear stability theory for the film frequency waves. The motion of the fluid in this

model was solved for analytically by matching. In If the liquid is non-volatile, and a two-dimensional orde to better r udersand model this and the ef. f order to better understand this model and the effects heating strip is inlaid in the plate, thermocapillarity of the contact line motion on the fluid motion we are

creates a dimpled interfaces. As the heat flux to the cr ntly d in numerial a ode to ole t

strip increases, the dimple deepens until dryout oc-cl ce to se

curs. A nonlinear theory for this steady state and its microscopic moving boundary problem. Initially a

lubrication model is being investigated. Next we plan

Engineering Research 36 1988
to consider the complete equations of motion and to OAK RIDGE NATIONAL LABORATORY

systematically incorporate these results into a macro- Engineering Physics and $1,075,000

scopic model of waves in partially saturated porous Mathematics Division 03-C

materials. Oak Ridge, TN 37831 87-5

84. Center for Engineering Systems Advanced UNIVERSITY OF NOTRE DAME Research (CESAR)

Department of Chemical Engineering $70,000 CR Weisbin

Notre Dame, IN 46556 01-C

-883 The Center for Engineering Systems Advanced Research (CESAR) conducts interdisciplinary long83. Study of Interfacial Behavior in Cocurrent range research and concept demonstration related to

Gas-Liquid Flows intelligent machines. CESAR provides a framework

MJ. McCready for merging concepts from the fields of artificial and

machine intelligence with advanced control theory.

The objectives of the work are to develop an under- There are two primary themes; robotic systems for

standing of and a quantitative method for describing identification, navigation, and manipulation in unthe waves which occur at the interface of separated structured environments: and multi-purpose plant

gas-liquid flows. These waves exert a significant in- management and maintenance.

fluence on the character of flows in the stratified and Specific FY 1988 research initiatives resulting in arannular flow regimes, however their fundamental na- chival publications have included: (1) Autonomous

ture is not well-understood. Navigation, Exploration and Recognition, (2)

Both theoretical and experimental techniques are Stability. Storage Capacity and Design of Nonlinear

being used. For very thin films, (e.g. annular flowcon- Continuous Neural Networks, (3) Learning by an

ditions) waves are relatively uniform and noninteract- Autonomous Robot at a Process Control Panel, (4)

ing and can consequently be described through the Treatment of Systematic Errors in the Processing of

use of solutions which predict the behavior for in- Wide Angle, Sonar Sensor Data, (5) Simulated Andividual waveforms. Observations of waves when the nealing Using the Mean Field Approximation, (6)

fluid is moderately viscous (15 cP) indicate that tran- Foundations of O-Theory: Measurements and Relasitions between wave types occur with increases in gas tion to Fuzzy Set Theory, and (7) Real-Time ImReynolds number and exhibit a relative insensitivity plementation of a Kinematic Gradient Projection

to liquid flow rate. Theoretical predictions using a Optimization Scheme for a Seven-Degree-oflinear theory agree well with measurements of Freedom Redundant Robot with Spherical Wrists.

wavelengths and wave speeds near the point of wave In addition, design of the HERMIES-III robot was

inception but begin to deviate as the gas velocity is in- completed and fabrication begun.

creased. Current work includes a comparison of experiments with solutions to a nonlinear wave

equation. For thicker films, (e.g. in stratified flows)

waves are random, exhibit a high degree of interaction PHYSICAL SCIENCES INC.

and can be treated in terms of their energy spectra. Dascomb Research Park $121,000

Experiments have shown that the most important P. O Box 3100 06-A

wave interactions are those between a wave and its Andover, MA 01810 884

first overtone and that film depth and gas shear significantly affect the rate at which these interactions 85. Experimental And Theoretical Studies Of

occur. An equation for the wave spectrum, which has Condensation In Multicomponent Systems

been derived based on the total wave energy, clearly M.B. Fsh, G. Wilemslk

demonstrates the importance of energy transfer,

energy input and dissipation in determining the shape This research program comprises experimental and

of the spectrum. theoretical studies of nucleation and condensation in

multicomponent gas mixtures. The program goals

are: 1) to improve basic understanding of binary

nucleation and droplet growth, 2) to stringently test

theories of binary nucleation at high nucleation rates

Engineering Research 37 1988
and under nonisothermal conditions, 3) to develop conditions for which the inner cylinder is removed

improved theories where needed, 4) to enlarge the and solidification is induced at a stationary or rotatdata base for systems of both fundamental and prac- ing end wall.

tical interest, and 5) to provide reliable means for A p o A primary objective of the work is to develop and predicting the behavior of mixtures used in practical vaiate a ove moe for the effects of application as to sh . x- validate a novel model for predicting the effects of applications such as turbo-machineiy. Experimental- applications as turbo-machiiy. such xperimental- convection on solidification in binary mixtures. Treatly, condensible vapors mixed with a carrier gas areon solid o h nd liid ion s asingle as con- ing solid, mushy and liquid regions as a single con- cooled in a supersonic nozzle to obtain much higher inuous domain h modl alid ontinm teo

binary nucleation rates than have been studied pre- to so atin h model appied convtinuum ork

viously. The nozzle is designed to ensure that steady- it to dimension nmeric sotions, calul

state nucleation occurs and to give satisfactory spatial t ions will be perormed to determine phase ront tions will be performed to determine phase front resolution of the temperature profile as determined ed eli, -e n development and related velocity, temperature and by interferometry. Laser light scattering combined eeo ent an elated veoit teperatre concentration fields over a wide range of operating with empirical calculations of the latent heat released nntion ied o wide range of operatig conditions. Predictions will be validated through during condensation is used to detect the "onset" of coii. ii i i

nucleation and to monitor subsequent droplet comparison with experimental results obtained for

growth. Construction of the flow and optical systems ransparen binary mixtures. Theexperiments will involve visual determinations of phase front develop- has been completed in previous years; data collection volve visual determinaons of phase front develop- is now being performed routinely. A new ther- ment and flow within the melt, as well as temperature

,i ~ ,y .w e -g , '' *~ wi and concentration measurements. The results are ex- modynamic theory of binary cluster composition has and o trto m rmnts. The resuts are e

been developed. Calculations with this theory have pe p i i i r

effects of convection on solidification phenomena established the feasibility of using bulk liquid mixture effects of onvecon on solidifcaon phenomena

surface tensions to compute nucleation onset (for such as macrosegregaton, while validaton of the

small rates) in adequeous alcohol and acetone mix- model should provide a useful computational tool for

tures, thus removing a severe deficiency of classical industrial processes involving the casting of binary

tu * ~~~res,~~~ thus materials. binary nucleation theory.

PURDUE UNIVERSITY PURDUE UNIVERSITY

School of Mechanical Engineering $ 85,000 SchoolofMechanicalEngineeng $115,000

West Lafayette, 47907 IN 01-C-B

87-3 85-4 87-3

86. Effect of Forced and Natural Convection on 87. HeatingandEvaporaon of Turbuent

Solidification of Binary Mixtures Liquid Films

F.P. Incropera Mudawwar

This project aims at studying transport phenomena This study deals with the influence of combined con- This project aims at studying ransport phenomena associated with turbulent liquid film flow. Experi- vection mechanisms on the solidification of binary associated with turbulent liquid fi E

mixtures in both rectangular and cylindrical ments have been performed with film undergoing sensible heating or interfacial evaporation and cor- geometries. The mechanisms include natural convec- g r i por relations have been developed for a wide range of tion driven by temperature and solute concentration rlaons have been developed for a wide range of operating conditions. To better understand the ef- gradients, as well as forced convection due to an ex- operating conditions. To better understand the ef- fects of interfacial waves on film motion a new high ternally imposed flow or a rotating surface. In the rec- fcts of interfaal waves on film moon a new high resolution fdm thickness probe has been developed. tangular geometry, solidification is induced at one or resolution film thickness probe has been developed both of opposing planar walls, with the ends capped Instantaneous measurements of film thickness have both of opposing planar walls, with the ends capped, b f

allowing for natural convection, or open, allowing for b o , probe design is expected to provide fim thickness

passage of an imposed flow and therefore combined probe design is expected to provide film thickness

measurements on an electrically heated test section. convection. For the cylindrical geometry, solidifica- measurements on an eleccally heated test section The remaining tasks of this project will involve obtain- tion is induced in the annular cavity between cooled Ts o je in

inner and/or outer tube walls, and the ends are ing simultaneous measurmentsof filmthickness and

capped. Combined convection is studied by solidify- liquid temperature to better understand the transient

variation of the heat transfer coefficient associated ing at one tube wall while rotating the other wall. In ra s, s

addition, the effects of convection are studied under wth film wavme ss. Pa r all el to this study simultaneous measurements of the instantaneous lonEngineering Research 38 1988
gitudinal and transverse velocity components and of steel. Strain aging was further investigated by relaxafilm thickness will be used to correlate a time- tion and strain-rate-jump tests at high temperature.

averaged eddy diffusivity profile which accounts for A finite deformation theory ofviscoplasticity based on

interfacial wave activity. overstress is being developed and is being implemented into a finite element computer program.

RENSSELAER POLYTECHNIC

INSTITUTE RENSSELAER POLYTECHNIC

Department of Mechanical Engineering, $125,000 INSTITUTE

Aeronautical Engineering & Mechanics 01-A Department of Nuclear Engineering $120,000

Troy, NY 12180-3590 88-3 and Science 01-C

Troy, NY 12180-3590 86-3

88. Inelastic Deformation and Damage at High

Temperature 89. An Analysis of the Closure Conditions for

E. Krempl Two Fluid Models of Two-Phase Flow

R.T. Lahey, Jr., DA. Drew

A combined theoretical and experimental investigation is performed to study the biaxial deformation and The objective of the analytical study being conducted

failure behavior of AISI Type 304 Stainless Steel is to investigate the constraints imposed on the

under low-cycle fatigue conditions at elevated closure conditions of two fluid models of two-phase

temperature. The purpose is to characterize the flow by:

material behavior in mathematical equations which

(1) The postulate of continuum mechanics. are ultimately intended for use in inelastic stress

analysis and life prediction. Creep-fatigue interaction (2) The second law of thermodynamics.

and ratchetting are of special concern. The long-term

goal is the development of a finite element program 3) Mathematical we-posedness.

that can directly calculate the life-to-crack initiation (4) Stability considerations.

of a component under a given load history. In particular, we plan to develop an analytical basis

The previously developed viscoplasticity theorybased on which unacceptable interfacial transfer laws and

on overstress (VBO) which uses neither a yield sur- parameters can be filtered out. We have now begun

face nor loading and unloading conditions will be aug- work on investigating some of the existing closure laws

mented to include the effects of recovery and aging. which are commonly used in two fluid models. ForThis constitutive equation will be combined with an mulation for the virtual mass force and the Reynolds

incremental damage accumulation law. It exists in stress are now being investigated. In addition,

uniaxial form and will be reviewed and extended to numerically-based algebraic manipulations are being

multiaxial, isotropic conditions. The theory will be employed to investigate the eigenvalues of curchecked against companion experiments. rentgeneration two-fluid models. It is felt that the

For the experiments, an MTS servohydraulic results of this research should significantly advance

axial/torsion test system is available together with an the state-of-the-art in the two fluid modeling of twoMTS Data/Control Processor. Induction heating (10 phase ows such that, in the future, well-posed

kHz) frequency), MTS biaxial grips and an MTS models can be developed which only exhibit inbiaxial extensometer will be used for the first time in stabilities of physical or

this study of biaxial deformation and failure behavior.

The biaxial test facility was checked out and is ready

for testing.

Uniaxial and torsional ratchetting experiments

showed considerable strain accumulation at room

temperature and they demonstrate that ratchetting is

due to viscous effects. Surprisingly, insignificant

ratchetting and rate sensitivity were observed at 550,

600 and 650°C for uniaxial tests. This unexpected

finding was attributed to strain aging in the stainless

Engineering Research 39 1988
THE ROCKEFELLER UNIVERSITY a turbulent fuel-air mixture, and the temperature field

Department of Physics $80,000 in a turbulent diffusion flame.

1230 York Avenue 06-C The turbulent combustion environments are modeled

New York,NY 10021 88-3 by adopting a stochastic rearrangement process to

simulate convective stirring, in conjunction with a

90. Some Basic Research Problems Related to deterministic representation of molecular diffusion

Energy and chemical reactions. Restriction of the computaE.G.D. Cohen tional domain to one spatial dimension facilitates the

inclusion of all relevant length scales in highThe project is concerned with the following objec- Reynolds-number flow simulations. This approach

tives: 1) The prediction of the transport coefficients avoids the difficulties that arise when the fine-scale

for mixtures of real fluids, using a new form of the processes are modeled separately. Work to date has

modified Enskog theory, 2) To develop a kinetic demonstrated that this approach reproduces salient

theory that allows a computation of the transport features observed in several turbulent mixing experiproperties of polydisperse fluid mixtures, based on ments. Further development and application of the

procedures developed for the thermodynamic method to combustion problems is in progress.

properties of such mixtures as well as on an extension Combustion of heterogeneous solids is treated by

of the Enskog theory for hard sphere mixtures; 3) To means of stochastic network-breakup models represtudy the eigenmodes in binary hard sphere fluid mix- senting, on a macroscopic scale, the disintegration of

tures in thermal equilibrium, for all mass ratios and a reacting particle into fragments, or on a microscopic

densities. The study will be based on the generalized scale, the thermochemical dissociation of a macroEnskog theory. The results will be compared with molecular fuel such as coal. Such models have been

laboratory and computer experiments; 4) A sys- formulated in work to date, and they are presently

tematic investigation of binary mixtures in the gaseous being validated based on comparison to coal pyrolysis

state--such as the noble gas mixtures--will be made to and oxidation measurements.

study the occurrence of a new type of sound, fast

sound, in these mixtures. This fast sound mode has

recently been predicted to exist in He-Xe mixtures; 5)

A critical study of cellular automata fluids is under- SANDIA NATIONAL LABORATORIES

taken that comprises not only their applicability to Combustion Research Facility $135,000

describe the flow properties of real fluids but also the Thermofuids Division 06-B

diffusion properties of particles moving on lattices in Lvermore, CA 94551-0098 87-3

the presence of randomly distributed stationary

obstacles. In view of the many unrealistic features of 92. Nonlinear Analysis of Ligament and Droplet

these automata fluids as compared to real fluids, at- Breakup

tempts will be made to incorporate into the existing B.R. Sanders, HA. Dwyer, D.S.

models more realistic features. Dandy

The objective of this research program is to study the

SANDIA NATIONAL LABORATORIES nonlinear fluid dynamics and transport processes

Combustion Research Facility $135,000 which govern the deformation and breakup of liquid

Thermofluids Division 06-B ligaments and large droplets. In particular, finiteLivermore, CA 94550 87-3 volume computations will be used to study the time

evolution of surface disturbances on a three-dimensional liquid element as it deforms and breaks up 91. Spatial Random Processes in Combustion under the influences of variable-property interfacial

A.R Kerstein tension, aerodynamic forces, liquid circulation, heat

transfer between phases, and vaporization. Since the

The goal of this project is to develop stochastic three-dimensional analysis provides all surface force

models which capture the dynamics of evolving spa- components, the drag coefficient will also be charactial structures observed experimentally in various terized for a family of non axisymmetric liquid elecombustion environments. Examples of such evolv- ments as they experience the highly nonlinear

ing structures are the surface morphology of a burn- transport processes mentioned above. The scope of

ing coal particle, the shape of a flame front traversing this research proposal is limited to computational

Engineering Research 40 1988
studies, however this research is closely tied to ex- of the fluid properties due to the motion of these parperimental research efforts at Sandia and elsewhere. tides. Previous treatments of suspensions have either

Two spray combustion experiments are beginning at been phenomenological or have used molecular

Sandia's Combustion Research Facility, one with a theories which do not have the advantages outlines

pulsed spray and one with a steady spray. Data from above.

these experiments will aid in verification of breakup

criteria predicted by the model under development.

Two single droplet experiments are also nearing com- SOLAR ENERGY RESEARCH

pletion, one utilizing a flat flame burner and one using

a levitator with laser ignition capabilities. These four IN lTITUTE

experiments will provided needed deformation, e r m a l c es R es e a r ch Br a ch $ 5 0 0 0 0

breakup, and transport data for liquid ligaments and 1 6 17 C O lv01 854

large droplets. Golden, CO 80401 85-4

94. Shear-Induced Instabilities in a

SCIENCE APPLICATIONS Double-Diffusive Partially Stratified Fluid

INTERNATIONAL CORPORATION F.Zangrando

Applied Plasma Physics and $85,000

Tehnology DiviPsi on 06- This basic experimental study concentrates on mixing

T0260 Cam D s P riv en 06-C mechanisms in a double-diffusive, stratified fluid sub- 10260 Campus Point Drive 88-2

10260 Campus Pot Drie 8-2 jected to the combined effects of bottom heating and San Diego, CA 92121 e me San~ Diego, CA 92121horizontal flow. The fluid contains two components

93. Transport Properties of Multi-Components (in this case, heat and salt) that contribute in an opFluids and of Suspensions posing manner to the fluid density and have sigI. Oppenheim, J. McBride nificantly different diffusivities (ratio of order 100).

The tasks proposed emphasize qualitative and quanThe first part of the research is to derive the non- titative observation of the behavior of the interfacial

linear hydrodynamic equations for multi-component layer between a double-diffusive stratification and an

fluids together with the conditions under which they initially well mixed region, both of arbitrary thickness,

are valid using the statistical mechanics theory of in the presence of buoyancy driven convection due to

mode-mode coupling. The second part of the re- bottom heating and of shear flow imposed on the

search is to study the transport properties of suspen- mixed region. The effect of each destabilizing comsions using recently developed methods for ponent, including line jet discharge and flow into a

eliminating fast variables in many-particle systems. A sink, will be first studied separately and compared

general non-equilibrium ensemble averaging has with results obtained with single-component

been used to generate macroscopic, nonlinear fluid- stratifications. The combined effect of buoyancy

transport equations with corrections due to long-time driven convection with a superposed lateral flow

tail effects (the formalism can be used to derive (recirculation) will then be studied in order to comhydrodynamic equations beyond the Navier-Stokes pare the various mixing mechanisms under similar exequations). The exact equations are nonlocal in both perimental conditions and to determine the

space and time and can be simplified to yield local entrainment at the interfacial boundary layer.

equations. The present theory which is restricted to

one-component fluids is to be generalized to include

the effects of multi-component fields. The aim is to

obtain the nonlinear hydrodynamic equations

together with the properties of the appropriate longtime tail phenomena. A new technique for the derivation of the Fokker-Planck equation governing the

probability density for the position and momentum of

a heavy (Brownian) particle in a fluid has been

developed. This technique is based on a scheme for

eliminating fast variables for phenomenological equations. The present research plan is to utilize this technique to obtain the Fokker-Planck equation for many

particles suspended in a fluid and for the perturbation

Engineering Research 41 1988
STANFORD UNIVERSITY STANFORD UNIVERSITY

Department of Mechanical Engineering $66,000 Department of Mechanical Engineering $165,000

Stanford, CA 94305-3030 01-B Stanford, CA 94305-3030 01-A

86-3 86-4

95. Heat Transfer in Three-Dimensional 96. Energy Changes in Transforming Solids

Turbulent Boundary Layers G. Hemnann, DM. Bamett

J. Eaton

The objective of this research is to investigate

Most boundary layers in practical systems are three- problems of stressed deformable solids in which comdimensional while most basic research on convective putations of energy changes and associated therheat transfer has focused on two-dimensional flows. modynamic (or configurational) forces have

The objectives of this work are to determine the ef- important implications.

fects of three-dimensionality on the'heat transfer behavior and how these effects may be modeled. A An anisotropic elastic boundary integral method has

eriesofsimplflow with successivelystrongertree- been developed and used to predict the existence of

dseries ofsimpale beflos w scessively ith songer tree- stable void lattices in irradiated FCC and BCC metals; numerical results are in close agreement with exThe first two experiments examined two-dimensional perimental observations quoted in the literature. An

boundary layers with large-scale embedded lon- apparent paradox in the dislocation literature has

gitudinal vortices. Detailed data including all com- been resolved. Although it should be well-known that

ponents of the mean velocity vector and Reynolds the energy of a (Volterra) dislocated solid is indestress tensor, spatially resolved heat transfer, pendent of the cut used to create it, virtually all such

temperature profiles, and skin friction have been ob- calculations in the literature are not cut-independent

tained. Pairs of moderate strength vortices cause sig- and are incorrect. Our resolution of this paradox has

nificant deviations from two-dimensional boundary important implications for the appearance of misfit

layer behavior in regions where the cross-flow is dislocations in epitaxial systems. A new investigation

strong. Both the momentum and thermal laws of the of energy changes and forces associated with dislocawall are violated showing that any models based on tions in anisotropic layered media is being undertwo-dimensional similarity laws will fail. The tur- taken, and the theory of interfacial waves in

bulent Prandtl number decreases strongly under the anisotropic elastic media is being extended to include

vortex. These effects are all tied to a reduction of the piezoelectricity.

boundary layer turbulence length scale. Conventional two-equation turbulence models fail to predict the An iteal equation method has been developed to * ., - .^ .. ~ i~-i . .. -study problems of interaction between holes and distorted Reynolds stress field. An improved model defects in elastostatics, including the calculation of was proposed but is not itself entirely satisfactory. dee elas atcs, nl the calculation o

energy release rates. An elementary theory of defecThe third experiment is a study of an initially 2D tivebeamsinbendingandofbarsintension,compresboundary layer which is skewed laterally by a pressure sion, and torsion has been developed. Based on an

gradient resulting in strong three dimensionality. extended circle theorem originally established in

Fluid mechanics measurements in the fully three- potential flow theory, the temperature distribution in

dimensional flow indicate that the important near- an infinite region containing a circular cavity (defect)

wall layers are strongly perturbed. The ration of the was determined in terms of the distribution existing in

Reynolds shearing stresses to the turbulent kinetic the same region without the cavity. The stress disenergy falls rapidly and the shear stress vector in the tribution induced by the presence of the defect was

plane of the wall is not aligned with the strain rate. shown to be universal, i.e., it depends essentially only

The system for measuring heat transfer in this flow is on the magnitude of the heat flux vector existing at the

being fabricated. Significant deviations from two- center of the defect before it was created.

dimensional behavior are expected.

Engineering Research 42 1988
STANFORD UNIVERSITY proach. In particular it addresses a water body that

W.W. Hansen Laboraotories of Physics $250,000 is continuously stratified in both temperature and

Stanford, CA 94305-3030 03-B salinity. The forcing is provided by a combination of

87-3 a lateral heat flux and a surface shear. Double-diffusive instabilities and mixed layer deepening occurs

in response to this forcing, resulting in changes to the

97. Nondestructive Testing vertical and horizontal fluxes of heat and salt. The

G.S. Kino goals are to (1) understand the initiation and evolu-

-tion of the double diffusive instabilities, (2) quantify The aim of this project is to arrive at techniques for the effects on the vertical fluxes, and (3) compare obcontactless nondestructive testing and range sensing. servations of the mixed layer deepening the existing

Devices which can be rapidly scanned over a surface data for singly stratified systems.

so as to detect flaws and measure their profiles are

badly needed. The measurement of parameters such The experimental component has to date conas surface roughness are also required. For this pur- centrated on the effects of lateral heating. A new 4.0

pose, we are developing acoustic sensors operating in m long and 0.8 m wide experimental tank, together

air and contactless photoacoustic techniques. with appurtenant facilities for controlling the initial

stratification, has been commissioned. The end wall

We have developed a newtype of PZT ceramic acous- of this tank is uniformly heated using a radiant source.

tic transducer with a quarter wavelength matching Fast response thermistor and conductivity probes are

layer of RTV rubber which operates in air in the fre- used to provide vertical profiles, and flow visualizaquency range of 18 MHz. The transducer itself has tion is provided by video imaging of dye in illuminated

been used for range sensing and for photoacoustic planes. Initial findings suggest that the nature of

measurements. As an example, it has enabled us to resulting convective intrusions is a function of two

measure regions of high surface recombination rates dimensionless stability parameters.

on semiconductors by varying the number of injected

carriers in a semiconductor, using a laser beam modu- The numerical component involves using a finite

lated at 2 MHz. We detect the rf term in the surface volume formulation of the non-linear Navier-Stokes,

temperature due to recombination. Similar techni- conservation of mass, and conservation of species

ques have been used by us to measure film thicknesses equations in three space dimensions and in time. The

and profiles. experimental results suggest that the high resolution

required to satisfactorily represent the intrusion inWe are now developing a new acoustic transducer terfaces will make a conventional modeling approach

operating in air which utilized a 1000 A thick pellicle very difficult, with the number of grid points required

of boron nitride as the detector of acoustic waves in to resolve the interfaces excessive, even in the context

the air. The deflection of the surface is measured by of modern supercomputers. For this reason work on

highly sensitive optical phase measurement of an op- implementing an adaptive gridding procedure has

tical beam reflected from the pellicle. The system is been commenced. Adaptive gridding allow the grid

as sensitive as our previous acoustic transducer, but to be selectively refined only in those areas where high

has the advantage that it can be operated over a resolution is required, thus facilitating large savings in

bandwidth from a few Hz to several MHz. both computational time and memory requirements.

STANFORD UNIVERSITY STANFORD UNIVERSITY

Department of Civil Engineering $137,000 Department of Mechanical Engineering $410,000

Environmental Fluid Mechanics Laboratory 01-B Stanford, CA 94305 03-B

Stanford, CA 94305-4020 87-3 88-4

98. Fluid Mechanics of Double Diffusive Systems 99. Diagnostics For Plasma Chemistry

J.R Koseff, R.L. Street, S.G. C.H. Kruger, MA. Cappelli

Schladow

This research is directed to the development of opti- This project is focused on processes that occur in a cal diagnostics for plasma chemistry and plasma

double-diffusive system subject to external forcing, processing with an emphasis on methods which can

using a combined experimental and numerical ap- assess and measure departures from local therEngineering Research 43 1988
modynamic equilibrium which can result from finite can be achieved for a particular range of frequencies

chemical reaction rates, elevated electron tempera- and amplitudes of external perturbations which yield

tures and densities, and radiation loss effects. The re- resonance effects and appropriate phase shifts of

search utilizes a newly implemented fluxes and forces. Bother theoretical and experimeninduction-plasma facility and existing high-power tal studies are planned on optimization of efficiency

lasers in the High Temperature Gasdynamics by choices of functional forms of external perturbaLaboratory. Optical methods will be developed for tions.

concentrations of chemical species in plasmas and

plasma parameters including electron density and

temperature. The research is intended to provide a STANFORD UNIVERSITY

more firm scientific basis for the understanding of Departmet of Civil Engineering S160,00

plasma chemistry and its practical development by Environmental Fluid Mecanics Laboratory 01-B

providing diagnostic techniques to monitor plasma Stanford, CA 94305-4020 87-2

parameters and the formation and removal of chemical species, so as to facilitate the rational design of

plasma processing facilities. 101. Momentum And Heat Transfer In A Complex

But Well-Defined Turbulent Flow Results to date from spectroscopic measurements of L We- JR Kos R.L. Street, R. Koseff the inductively coupled plasma show differences between Boltzmann excitation temperatures and those inferred ll as.sung ti . .A basic study of a three-dimensional, recirculating inferred assuming local thermodynamic equilbrium. flow with variable density effects is being conducted

Measurements of thera ra aiue n strength i in a lid-driven cavity. The overall objectives of the reargon indicate an order-of-magnitude difference search are (1) an improved understanding of the infrom values reported earlier at temperatures of inter- fluence of longitudinal vortices on heat transfer in the

est in plasma processing. This difference has been in- cavity and of the interaction between forced and

terpreted in terms of nonequilibrium effects in the natural convection processes, (2) achievement of

earlier experiments and an upper-bound limit with three-dimensional numericalsimulation of rerculatrespect to the decay of radiation source strength with ing natural, and mixed-convection fows, and (3) undecreasing temperature, derstanding the effects of cavity geometry on

momentum and heat transfer processes in such flows.

STANFORD UNIVERSITY The present major focus is on extending the work on

Department of Chemistry 109 0 square cavities (depth equal to width) to cavities of

Stanford, CA 94305 06-C variable depth. Physical experiments are being per- 86-3 formed in a lid-driven cavity facility using water as the

working fluid. Measurements include those obtained

by laser-Doppler anemometry, microthermocouples,

100. Reduction of Dissipation in Combustion and heat-flux meters, and liquid crystal and polystyrene

Engines bead flow visualization. Image processing is being

I. Ross used to extract quantitative information from the flow

visualization photographs.

Research is concerned with the issue of the enhance-s ae ao bd Numerical experiments are also being performed in ment of power output in thermal and chemical en-ing pe ad

gines by means of external perturbations of support of specific physical experiments and on a side-wall-heated natural convection flow. These constraints coupled to nonlinearities of the cn ti f. T constraints coupled to nonlinearities of the numerical experiments are being conducted using the

mechanism of the engine. Theoretical possibility of an SEiAL 1code. This time-accute, excit code SEAFLOS1 code. This time-accurate, explicit code increase in power output of a thermal engine driven features a revised QUICK formulation and the Inby a chemical reaction by means of external periodic omlete Choles Conuate radient ICC complete Cholesky Conjugate Gradient (ICCG) variations of reactant influx has been confirmed by Method or the mul te ue fr sing the Method or the multigrid technique for solving the preliminary experiments. The power output of an en- t

pressure equation. These last-mentioned techniques gine is necessarily accompanied by dissipation due to pressure equation. hese last-mentioned techniques

irreversible processes essential for power production. are producing sgncant savings in simulaton runHence an increase in power output by means of exter- time

nal perturbations usually implies a decrease in dissipation but may also come about due to a change in

the final state of the system. Increases in efficiency

Engineering Research 44 1988
STANFORD UNIVERSITY We have determined the dynamics of transition from

Department of Mechanical Engineering $86,000 Hamiltonian to dissipative systems in the chaotic

Design Division 03-A regime. As the Hamiltonian limit is approached,

Stanford, CA 94305 86-3 strange attractors disappear in an orderly fashion as

dissipation is reduced. There exist a set of universal

Jacobians Jn' where the 2n piece strange attractors

102. Global Optimization of Non-Posynomial disappear. This phenomenon is universal as we have

Design Models proven using renormalization calculations, in the

DJ. Wilde vicinity of the universal Hamiltonian function T*. In

fact we have shown that all phenomena possess a

Geometric Programming optimization problems can universal scaling in the K-J parameter space, where K

be solved by maximizing a dual function subject to is the strength parameter and J is the Jacobian.

linear constraints. This dual, although convex, is only

poorly approximated by a homogeneous quadratic We studied universal strange attractors, homoclinic

form, but allowing axis rotation gives a remarkably and heteroclinic crises, Liapunov exponents and wingood fit by the method of least squares. The resulting dows. Everything scales along fan lines in parameter

quadratic program has a closed form matrix solution space in a well defined manner.

to be used iteratively. Proof of convergence, conver- Physical systems that produce two dimensional maps

gence rate estimation, and computer testing on en- are of course different from the universal ones. We

gineering design problems are in Shensheng Zhang's have found recently that such systems exhibit exPh.D. dissertation "Generalized Polynomial Op- tremely rapid convergence to the universal sequence

timization -in an Augmented Primary Space using of Jn values. Among the systems studied were the

General Quadratic Approximation" and in two re- driven damped pendulum, the bouncing ball, the parsearch papers based on it. tide in the standing wave field. All systems studied exA different approach to global optimization is being hibited the rapid convergence to the universal system

studied by Ph.D. candidate Yong Se Kim. His re- as predicted. The fundamental theory of dissipative

search concerns expressing a non-convex set unique- dynamical systems, represented by two dimensional

ly as a difference of convex sets. Although the maps has been established.

problem is motivated by the three-dimensional

problem of computer characterization of machine

parts, it may be extendable to more dimensions. This UNIVERSITY OF TEXAS AT AUSTIN

would allow non-posynomial optimization problems Center for Studies in Statistical Mech. $100,000

to be decomposed into convex posynomial problems Austin, TX 78712 06-C

separately solvable by known efficient algorithms 88-3

STEVENS- I ~NSTITIUTE OF 104. The Behavior of Matter Under

~~STEVENS INSTITUTE OF ~Nonequilibrium Conditions: Fundamental

TECHNOLOGY Aspects and Application in Energy-Oriented

Department of Physics and Engineering $ 64,000 - Problems

Hoboken, NJ 07030 06-C I. Prgogine

87-4

This research aims at new fundamental developments

103. Investigation of Transitions From Order to in the area of non-equilibrium phenomena, as well as

Chaos in Dynamical Systems at various applications to disciplines in which complex

G. Schmidt systems giving rise to instabilities and bifurcations are

of current and primary concern. Special emphasis is

The transition from order to chaos in dynamical sys- being placed onthre principal directions. Firstthe

ters of few degrees of freedom are studied, using methods of nonlinear dynamical systems will be aptheory, numerical computation and a laboratory ex- - pied to investigate the transition phenomena occurperiment as tools of this investigation. This workis ing in physico-chemical problems such as

nearly completed and we are tooling up to study more atmospheric dynamics, the Belusov-Zhabotinski

complex systemswith many degrees of freedom. reaction and the oxidation of hydrocarbons in the

gaseous phase. Both perturbative and global techniques will be applied, since current experimental

Engineering Research 45 1988
evidence suggests that some of these transitions in- These laboratory experiments and numerical and

volve chaotic dynamics and homoclinic orbits. analytic studies of models should provide general inSecond, problems arising in connection with selection sights into spatiotemporal patterns in nonequilibrium

of nonequilibrium states will be analyzed. In par- systems.

ticular, the effect of extremely small influences in the

selection of symmetry-breaking states -- which are

realized in chemical, electronic, and other systems -- UNIVERSITY OF TEXAS AT AUSTIN

will be studied, taking both additive and multiplica- Department of Mechanical Engineering $134,000

tive fluctuations into consideration. The implication and Center for Energy Studies 01-B

of the results for the origin of biomolecular chirality Austin, TX 78712 87-3

will be assessed. Collaborative experiments are

planned to substantiate the theoretical developments.

Third, special attention will be focused on the 106. Self-Shielding of Surfaces Irradiated by

problem of combustion. A fundamental analysis of Intense Energy Fluxes

this phenomenon, from both the standpoint of the P.L Varghese, JJ.R Howel

theory of dynamical systems and the standpoint of

stochastic theory, is still lacking. In the proposed re- The objective of this work is to study the interactions

search, the effect of stochastic perturbations, of in- between high-temperature, high velocity plasmas and

homogeneities and of internal fluctuations during the solid surfaces. There are two main thrusts in the

process of ignition, in which the system is expected to program: numerical modeling and experimental testpresent a high sensitivity, will be analyzed using ing of model predictions. This calibrated modeling

Semenov's model for combustion as well as more procedure will provide information for reliable

realistic models. A fundamental theory of nucleation predictions of plasma-surface interactions with exof flame fronts is expected to be one of the outcomes tremely high energy fluxes. The work will be conof these developments. ducted in unique facilities at the University of Texas

at Austin. Plasmas at high temperatures (greater than

10,000 K) and densities (1015/cm3) will be accelerated

UNIVERSITY OF TEXAS AT AUSTIN in capacitor or homopolar generator driven rail guns.

Department of Physics $142,000 These plasmas will be studied using high speed emisAustin, TX 78712 06-C sion spectroscopy and laser induced fluorescence in

87-5 order to determine the composition and temperature

of the plasma, and to detect the development and influence of the vapor shield produced by the surface

105. Complex Temporal and Spatial Patterns in when it is heated rapidly. The experimental results

Nonequilibrium Systems will be used to modify and refine the numerical model

H.L. Swinney so as to provide an accurate and reliable predictive

tooL The model will characterize the basic physical

Dynamical systems methods are being developed and processes that govern the interaction between a surused to characterized nonequilibrium processes and face and a transient energy flux. Because it is funto address outstanding unresolved questions regard- damentally based, rather than empirical, the model

ing bifurcations and chaos, especially in reaction-dif- will be more readily adaptable to a wide range of situafusion systems. An information-theoretic property, tions in which surfaces are irradiated byintense enerthe mutual information, is being examined as a means gy fluxes. The model developed during the course of

for detecting and quantifying spatiotemporal chaos. this work will allow better design of devices such as

The work has demonstrated that information on high current density brushes and switch gear, arc

dynamics deduced from noisy data can be used to welding apparatus, rail guns, and fusion reactors.

reduce the noise in those data. These tools from

dynamical systems and information theory are being

applied to data obtained in laboratory experiments on

homogeneous systems and on extended systems. A

novel unstirred chemical reactor has been designed

for studies of the development and evolution of

chemical spatial patterns, and experiments with this

reactor have yielded the first sustained chemical spatial patterns in a controlled laboratory environment.

Engineering Research 46 1988
TUFTS UNIVERSITY tion spectroscopy, Laser Induced Fluorescence

Department of Mechanical Engineering $ 55,000 Spectroscopy (LIFS), and Coherent Anti-Stokes

Medford, MA 02155 01-A Raman Spectroscopy (CARS) are being used to

86-2 determine, in situ, the reactive plasma composition,

temperature, and species concentration and distribution in the gas phase. The second task includes use of

107. Effective Elastic Properties of Cracked Solids Auger Electron Spectroscopy (AES), Ion Scattering

M. Kachanov Spectroscopy (ISS), Secondary Ion Mass Spectroscopy (SIMS) and other complementary techniques The knowledge of effective elastic properties of solids for detailed coating characterization. These are being

with cracks appears to be of increasing engineering combined with physical measurements of coating surimportance. Extensive microcracking in structural face smoothness, density, hardness (state-of-the-art

elements working under conditions of high tempera- nanoindenter apparatus) and adherence (UTRC custures or irradiation, microcracking in composite tom built pin-on-disc apparatus). These combined

materials under fatigue conditions may noticeably tasks will allow a correlation of the PACVD

reduce the stiffness of the material and make it an- parameters with their required coating properties,

siotropic. Understanding and prediction of these thus providing a predictive capability that is severely

changes are essential for proper design and strength lacking in the present science base of advanced

and lifetime assessments. protective coatings. Results to date include: 1)

A new approach to many cracks problems based on fabrication of a 5 kW rf PACVD reactor system ininterrelating the average tractions on individual tegrated with a completely oil-free, high vacuum syscracks is introduced. Its advantages are that it yields tem (ultimate 10-8 torr); 2) exploratory spectral

simple analytical results which are quite accurate up emission surveys for major molecular band and

to very high crack densities and that it can be applied atomic line identification; 3) development of a

to crack arrays or arbitrary geometry. Relation be- colinear, scanned, narrowband CARS system; 4) imtween deterioration of elastic properties and plementation of a ultramicrohardness tester and ad-

"damage" is discussed. hesion test apparatus and 5) demonstrated CARS

collibrator sensitivity PSCVD reactor of 10m Torr.

UNITED TECHNOLOGIES RESEARCH WASHINGTN S E

~~~~CENTER WASHINGTON STATE UNIVERSITY

CEPropulsion Science Laboratoy $185 Department of Mechanical Engineering $ 0 Propulsion Science Laboratory 85,0 lman WA 99164-2920 01-B

East Hartford, CT 06108 06-A 86-3

86-3

108. Laser Diagnostics Of PACVD Processes 109. Particle Dispersion by Ordered Motion in

W C. Roman, J. H. Stufflebeam, M.ng Layers

F. A. Otter, A. C. Eckbreth

This research program is directed towards under- The objectives of this research are to perform a com- This esearch program is directed towards underprehensive experimental investigation of the fun- standing the role of quasi deterministic large scale

damental bum none reactive plasma assisted vortices in the dispersion of particles by turbulent damental nonequilibrium reactive plasma assisted

chemical vapor deposition (PACVD) process ap- miing layers. The primary objective of this experimental study is to determine the influence and im- plicable to hard face coatings. Based on its superior prmentalstudyistodetermnethenfuence andimerosion resistance, TiB2 was selected as the initial poance of these vortex structures on the particle

coating for deposition onto a titanium alloy substrate dispersion process over a range of particle and flow

(Ti-6A1-4V). In task I, novel non-intrusive laser diag- parameters. It is hypothesized that if the time scale

associated with the vortex motion and the particle nostic techniques (e.g. optical emission and absorp-

* UTRC consultant, presently at University of Connecticut/Institute of Materials Science

Engineering Research 47 1988
relaxation time are of the same order, significantly en- is closely coordinated with the Carnegie-Mellon

hanced particle dispersion may occur. University Combustion Laboratory.

The experiments employ both high speed

photographic methods and laser velocimetry techniques. The experimental results demonstrate that UNIVERSITY OF WISCONSIN

large scale vortex structures dominate the particle dis- Mechanical Engineering Department $100,000

persion process for intermediate size particles. The Madison, WI 53201 01-C

experimental dispersion patterns appear qualitative- 87-3

ly similar to numerical results obtained using time dependent numerical simulation techniques. Current Current 111. Interfacial Area and Interfacial Transfer in

efforts involve quantifying the experimental results Two-Phase Flow Systems

for more detailed comparisons with numerical Two-PhaseFlowSystems G. Kocamustafaogullari, M. Ishii predictions. Initial experimental results also G.Kam

demonstrate that substantial modifications of the particle dispersion process can be achieved using con- tide dispersion process can be achieved using con- The research program is ajoint effort by the members trolled forcing techniques. of the University of Wisconsin-Milwaukee and ArThe primary anticipated result of this study is a new gonne National Laboratory. The objective of the rephysical model for interpreting and predicting par- search program is to develop instrumentation

tide dispersion in unbounded turbulent shear flows. techniques, a data base and predictive methods for

New techniques for controlling or modifying the dis- describing the interfacial structure of horizontal and

persion of particles in turbulent flows are a possible vertical two-phase flow, such as flow pattern transioutcome of this research program. tions, interfacial area concentration and interfacial

wave structure. The special emphasis will be placed

on developing local interfacial area concentration

WESTINGHOUSE R&D CENTER measurement techniques, and two-phase flow-patChemical & Process Development Dept 151,000 tern transition criteria. The latter include 1) scaling Chemical & Process Development DepL. $151,000

1310 Beulah Road 01-C criteria in terms of systems size and fluid properties

Pittsburgh, PA 15235 86.3 2) entrance geometry and developing flow effects, and

3) rational procedure and design criteria for predicting these effects.

110. The Design of a Cylindrical Film Chemical Te Den of a C rcal F Cecal To achieve the objectives, the technical approach is

RM. Roidt divided into three parts. The first part deals with

theoretical modeling of the interfacial area and flowpattern transitions based on physical mechanisms. This research is to investigate the basic characteris- pattern transitions based on physical mechanism The second part is concerned with designing and per- tics of a cylindricall film chemical reactor; i.e., a fall- The sond prt is onern th des g ad pe- forming horizontal and vertical two-phase flow ex- ing annulus of liquid within which gases and sprays ormin ntal and vertical t-hase ow periments to generate benchmark data using flow

may be injected to react chemically. The program is p ents to generate enmarkata using flo visualization and objective measurements. F'mally, primarily experimental and focuses primarily on film

the third part deals with incorporating the results of stability, internal gas entrainment rates, and geometric in the film variat configuration. Studies theoretical and experimental studies to examine and

hageometric variations ,m an30cdietrn- verify the validity of proposed flow-pattern transition have been completed on 5,10, and 30 cm diameter an- mechanisms and interfacial area concentration and area null with .5,1, and 2 mm annular clearances. Ranges

of stable film operation with various liquid flow rates m

and internal gas injection rates have been inves- The results of this research program will provide intigated. The primary focus at present is the deter- formation in horizontal and vertical two-phase flow

mination of the conditions under which internal fundamentals and information critical to the design of

sprays may be entered into the reaction volume to en- advanced two-phase flow systems.

hance surface area reactions for such application

areas as scrubbers. The induced internal gas flows

caused by the sprays are quite disruptive of film

operation and various injection techniques are being

investigated to alleviate these interactions. This work

Engineering Research 48 1988
UNIVERSITY OF WISCONSIN

Department of Chemical Engineering $106,000

Madison, WI 53706 03-A

86-3

112. The Development of Process Design and

Control Strategies for Energy Efficiency,

High Product Quality, and Improved

Productivity in the Process Industries

W.H. Ray

The process industries are having great difficulty

competing in the world market because of high energy costs, high labor rates, and old technology for many

processes. This project is concerned with the

development of process design and control strategies

for improving energy efficiency, product quality, and

productivity in the process industry. In particular, (i)

the resilient design and control of chemical reactors,

and (ii) the operation of complex processing systems,

will be investigated. Major emphasis in part (i) will

be on two important classes of chemical reactors:

polymerization processes and packed bed reactors.

In part (ii), the main focus will be on developing

process identification and control procedures which

allow the design of advanced control systems based

on limited process information and which will work

reliably when process parameters change in an unknown manner. Specific topics to be studied include

new process identification procedures, nonlinear

controller designs, adaptive control methods, and

techniques for distributed parameter systems. Both

fundamental and immediately applicable results are

expected. The theoretical developments are being

tested experimentally on pilot scale equipment in the

laboratory. These experiments not only allow improvements in theoretical work, but also represent

real life demonstrations of the effectiveness of the

methods and of the feasibility of implementing them

in an industrial environment. The new techniques

developed in this project will be incorporated into

computer-aided design packages and disseminated to

industry. Therefore, it is expected that the work will

have an impact on industrial practice.

Engineering Research 49 1988
BUDGET NUMBER INDEX

Mechanical Sciences:

01-A Solid Mechanics: macroscopic aspects of elastic and plastic

deformations, and crack propagation

01-B Heat Transfer

01-C Fluid Mechanics

01-D Tribology

Control Systems and Instrumentation:

03-A Control systems, large scale systems

03-B Instrumentation for hostile environment, and NDE

03-C Intelligent systems

Engineering Data and Analysis:

06-A Thermophysical properties and processes

06-B Combustion

06-C Non-linear dynamics and engineering analysis
Project Titles

01-A

Bounds on Dynamic Plastic Deformation ............................. ............................. 2

Micromechanical Viscoplastic Stress-Strain Model with Grain

Boundary Sliding .......................................................................................................... 12

A Micromechanical Viscoplastic Stress-strain Model with

Grain Boundary Sliding .............................................................................................. 14

Elastic-Plastic Fracture Analysis Emphasis on Surface Flaws ..................................... 17

Continuous Damage Mechanics II .................................................................................. 19

Modeling and Analysis of Surface Cracks ...................................................................... 29

Energetics of Comminution ........................................................................................... 29

Inelastic Deformation and Damage at High Temperature ......................................... 39

Energy Changes in Transforming Solids ............. ........................... ............ 42

Effective Elastic Properties of Cracked Solids .............................................................. 47

01-B

The Turbulent Transport of Heat Within a Longitudinal

Vortex/Boundary Layer Interaction .............................................................................. 4

Radiation in Particulate Systems ....................................................................................... 5

High Flux Film and Transition Boiling ........................................ ............. 15

Heat Transfer to Aqueous Polymer Solutions ............................................................... 19

The Impact of Separated Flow on Heat and Mass Transfer ........................................ 31

Thinning And Rupture of a Thin Liquid File on a Horizontal

H eated Solid Surface ................................................................................................. 36

Heating and Evaporation of Turbulent Liquid Films .................................................. 38

Heat Transfer in Three-Dimensional Turbulent

B oundary Layers ....................................................................................................... 42

Fluid Mechanics of Double Diffusive Systems...............................................................43

Momentum And Heat Transfer In A Complex But

Well-Defined Turbulent Flow .................................................................................... 44

Self-Shielding of Surfaces Irradiated by Intense

E nergy Fluxes ............................................................................................................. 46

Particle Dispersion by Ordered Motion in Mixing

L ayers ........................................................................................................................... 47

Engineering Research 1988
Project Titles

01-C

Theoretical/Experimental Study of Stability Control......................................................1

Basic Studies of Transport Processes in Porous Media ................................................. 6

Parameterization of Intermittent Turbulence and the

V orton M ethod ............................................................................................................... 8

Turbulent Structure in Liquid Streams Bounded by

a Free Surface and a Solid Wall ................................................................................. 9

Experimental And Theoretical Studies Of Vertical

Annular Liquid Jets ........ .................................................. 10

Droplet Motion in Numerically Simulated Turbulence ............................................... 11

Experiments in Turbulent Mixing ................................................................................... 13

Subcooled Sprays in a Vapor Environment-Tests of the

Two-Fluid Model for Two-Phase Flow .................................................................. 13

Comparative Study of the Vorticity Field in Turbulent

Flows: Theory, Experiments, Computations ............................................................. 14

Gas-Liquid Flow in Pipelines ........................................................................................... 18

Lattice Gas Hydrodynamics: Theory and Simulations .............................................. 22

The Use of Optical Flow Fields in Establishing Stereo

Correspondence ............................................................................................................ 22

Comparative Study of the Vorticity Field in Turbulent

Flows: Theory, Experiment, Computations ............................................................ 23

Lubricated Pipelining ....................................................................................................... 31

Residence Time Distribution Approach to the Study

of Free Convection in Porous Media.......................................................................... 32

Comparative Study of Vorticity Field in Turbulent Flows .......................................... 33

Periodically Structured Multiphase Flows and Hydrodynamic

Instabilities in Narrow Channels ................................................................................ 34

Attenuation of Waves in Partially Saturated Porous Solids ........................................ 36

Study of Interfacial Behavior in Cocurrent Gas-Liquid Flows .................................... 37

Effect of Forced and Natural Convection on Solidification of

Binary Mixtures........................................................................................................... 38

An Analysis of the Closure Conditions for Two Fluid Models

of Two-Phase Flow ..................................................................................................... 39

Shear-Induced Instabilities in a Double-Diffusive Partially

Stratified Fluid .............................................................................................................. 41

The Design of a Cylindrical Film Chemical Reactor ................................................. 48

Interfacial Area and Interfacial Transfer in Two-Phase Flow Systems ..................... 48

Engineering Research 1988
Project Titles

01-D

The Development of a Friction Model Predicting the Sliding

Behavior of Material Pairs, Especially at Low Temperatures.................................28

03-A

Strategies for Optimal Redesign In a Changing Environment .................................... 10

Integrated Sensor Model Development for Automated Welding .............................. 18

Model Building and Control of Large Scale Systems .................................................. 18

Vibrational Control of Chemical Reactors: Selectivity Enhancement,

Stabilization and Improvement of Transient Behavior .......................................... 20

The Creation of Multi-Degree-of-Freedom Mechanisms for Robotic

A pplications................................................................................................................. 23

Screening Alternative Control Structures for Plant Control System ......................... 24

Synthesis of Heat and Work Integration Systems for Chemical

Process Plants ............................................................................................................... 27

In-Process Control of Residual Stresses and Distortion in Automatic

W elding ........................................................................................................................ 28

Global Optimization of Non-Posynomial Design Models............................................45

The Development of Process Design and Control Strategies for Energy

Efficiency, High Product Quality, and Improved Productivity in the

Process Industries ................................................................................................... 49

03-B

New Ultrasonic Imaging and Measurement Techniques for NDE .............................. 1

An Automated Flow Calorimeter for Heat Capacity and Enthalpy

Measurements at Elevated Temperatures and Pressures ........................................ 12

Nondestructive Characterization of Fracture Dynamics and Crack Growth 16

Applications of Molecules as High Resolution, High-Sensitivity

Threshold Electron Detectors .................................................................................... 20

Metal Transfer in Gas Metal Arc Welding .................................................................... 25

Multivariable Control Of The Gas-Metal Arc Welding Process .............................. 28

Thermophysical Property Measurements in Fluid Mixtures ....................................... 33

Effects of Crack Geometry and Near-Crack Material Behavior on

Scattering of Ultrasonic Waves for QNDE Applications ........................................ 35

N ondestructive Testing ..................................................................................................... 43

Diagnostics For Plasma Chemistry .................................................................................. 43

Engineering Research 1988
Project Titles

03-C

Center for Engineering Systems Advanced Research (CESAR) ............................... 37

06-A

In-Flight Measurement of the Temperature of Small, High Velocity

Particles ....................................................................................................... 15

Experimental Measurement of the Plasma/Particle Interaction ................................ 17

Design and Synthesis of Reactive Separation Systems ................................................ 24

High Temperature Gas-Particle Reactions ................................................................... 26

Plasma Reduction of Metallic Oxides ......................................................................... 26

Mathematical Modelling of Transport Phenomena in Plasma Studies ..................... 30

Neutron Scattering From a Sheared Liquid: a Proposal to Construct

the Shearing Apparatus ................................................................................................ 32

Transport Properties Of Disordered Porous Media From The

M icrostructure .............................................................................................................. 35

Experimental And Theoretical Studies Of Condensation In

Multicomponent Systems ........................................ .......................... 37

Laser Diagnostics Of PACVD Processes ....................................................................... 47

06-B

Combustions and Heat Transfer in Porous Media ........................................................ 2

Structure and Stabilization of Premixed and Diffusion Flames.....................................5

Studies in the Combustion and Breakup of Transverse Liquid Jets and Fuel

D roplets ................................................................................................................................... 6

Fuel Droplets Subject to Straining Flow .......................................................................... 8

Controlled Combustion ................................................................................................... 21

Turbulent Premixed Flame Study .................................................................................... 25

Analysis of Transport Mechanisms in Dense Fuel Droplet Sprays ........................... 35

Spatial Random Processes in Combustion ..................................................................... 40

Nonlinear Analysis of Ligament and Droplet Breakup ............................................... 40

Engineering Research 1988
Project Titles

06-C

Diffusion, Fluid Flow, and Sound Propagation in Disordered Media ......................... 2

Two Studies of Nonlinear Processes in Irreversible Thermodynamics ....................... 3

Investigation of Secondary Motions and Transition to Turbulence

in Buoyancy-Driven Enclosure Flows with Streamline Curvature ............................ 4

Self-generated Stochastic Heating in an RF Discharge ................................................. 5

Wave Turbulence and Self-Localization in Continuous Media.....................................7

Nonlinear Dynamics in Dissipative Systems ........................................ ....................... 7

The Stochastic Trajectory Analysis Technique (STAT) Applied to

Chemical, Mechanical and Quantum Systems............................................................8

Bifurcations and Patterns in Nonlinear Systems .............................................................. 9

Topics in Finite-Time Thermodynamics ......................................................................... 11

Fundamentals and Techniques of Nonimaging Optics for Solar

E nergy C oncentration ................................................................................................. 11

Higher Dimensional Nonlinear Dynamics ..................................................................... 14

Modeling of Thermal Plasma Processes.......................................................................... 16

Studies in Nonlinear Dynamics ....................................................................................... 21

Study of Magnetostatic Problems in Nonlinear Media with Hysteresis ..................... 22

Mixing of Viscous Fluids: Behavior of Microstructures and Chaos ........................... 24

A Parity Simulator for Nuclear Power Plant Dymanics ............................................. 27

Macrostatistical Hydrodynamics ........................................ ..................... 30

Thermal Plasma Processing of Materials ........................................ ............ 31

Topics in Physico-Chemical Hydrodynamics............................................................... 34

Some Basic Research Problems Related to Energy.................................................... 40

Transport Properties of Multi-Components Fluids and of Suspensions ................ 41

Reduction of Dissipation in Combustion and Engines ............................................. 44

Investigation of Transitions From Order to Chaos in Dynamical Systems ............... 45

The Behavior of Matter Under Nonequilibrium Conditions:

Fundamental Aspects and Application in Energy-Oriented Problems ............... 45

Complex Temporal and Spatial Patterns in Nonequilibrium System ........................ 46

Engineering Research 1988
Principal Investigators

H.D.I. Abarbanel 7 Y. Iwasa 28 I. Prigogine 45

J.D. Achenbach 35 JA. Johnson 16,18 S. Putterman 7

G. Ahlers 9 M. Jones 32 J.I. Ramos 10

S.H. Alajajian 20 E.H. Jordan 12 J.D. Ramshaw 16

R.T. Allemeir 16 D.D. Joseph 31 V.H. Ransom 16

S. Banerjee 9 M. Kachanov 47 W.H. Ray 49

S.G. Bankoff 36 A.R. Karagozian 6 E.L. Reiss 1

BA. Barna 16 A.N. Kaufman 21 W.G. Reuter 17

D.M. Barnett 42 J. Keck 25 L.D. Reynolds 17

T. Basar 18 A.R. Kerstein 40 HJ. Richter 13

R.S. Berry 11 J. Kestin 3 R.M. Roidt 48

L.T. Biegler 10 T. Keyes 2 W. C. Roman 47

P.P. Bolsaitis 26 J. Kim 14 J. Ross 44

H. Brenner 30 G.S. Kino 43 B.R. Sanders 40

D.S. Cannell 9 C. Kleinstreuer 35 S.G. Schladow 43

MA. Cappelli 43 G. Kocamustafaogullari 48 G. Schmidt 45

I. Catton 6 P. Kokotovic 18 J.M.H. Sengers 33

W. Cheng 25 J.R. Koseff 43,44 K. Seshadri 8

N. Chigier 10 D. Krajcinovic 19 C.B. Shaw 17

A. Chutjian 20 E. Krempl 39 G.I. Sivashinsky 34

A. Cinar 20 C.H. Kruger 43 H.B. Smartt 18

E.G.D. Cohen 40 R.T. Lahey, Jr. 39 S.C. Snyder 17

D.S. Dandy 40 C.K. Law 5 R.L. Street 43,44

S.H. Davis 36 E. Levich 33 J.H. Stufflebeam 47

M.F. Doherty 24 PA. Libby 8 H.L. Swinney 46

J.M. Douglas 24 AJ. Lichtenberg 5 J. Szekely 26,30

DA. Drew 39 MA. Lieberman 5 D.O. Thompson 1

J.H. Duncan 22 K. Lindenberg 8 G.L. Thompson 10

HA. Dwyer 40 R.G. Littlejohn 21 C.L. Tien 5

T.W. Eagar 25 W.R. Lloyd 17 T.W. Tong 2

J. Eaton 42 C.M. Maldarelli 34 S. Torquato 35

A.C. Eckbreth 47 M.F. Malone 24 T.R. Troutt 47

PA. Eibeck 4 K Masubuchi 28 L. Tsai 23

J.F. Elliot 26 I.C. Mayergoyz 22 S.P. Vanka 1

L.B. Evans 27 J. McBride 41 P.L. Varghese 46

H. Fenech 9 FA. McClintock 29 K.P. Walker 14

J.R. Fmcke 15 MJ. McCready 37 J.M. Wallace 23

M.B. Frish 37 J.B. McLaughlin 11 G.B. Wallis 13

U. Frish 22 MJ. Miksis 36 Z. Warhaft 13

RJ. Goldstein 31 LA. Mondy 30 C.R. Weisbin 37

A.K. Graham 30 I. Mudawwar 38 BJ. West 8

S. Graham 17 T.M. Mulcahy 1 A.W. Westerberg 10

J.M. Greene 14 E.A. Novikov 8 DJ. Wilde 45

I.E. Grossmann 10 JJ. O'Gallagher 11 G. Wilemski 37

HJ.M. Hanley 32 NA. Olien 33 FA. Williams 8

TJ. Hanratty 18 A.K. Oppenheim 21 L.C. Witte 15

K.F. Hansen 27 I. Oppenheim 41 R. Winston 11

D.E. Hardt 28 OJ. Orient 20 J. Wolfe 32

J.P. Hartnett 19 F. A. Otter 47 V.F. Yesavage 12

B. Hasslacher 22 J.M. Ottino 24 G.K. Youngdahl 2

G. Herrmann 42 D.M. Parks 29 F. Zangrando 41

J.R. Howell 46 R.E. Peck 2

D.K. Hsu 1 R. Perkins 32

JA.C. Humphrey 4 C. Peterson 29

A.K.M. Hussain 14 E. Pfender 31

F.P. Incropera 38 Y. Pomeau 22

M. Ishii 48 S. Pope 25

Engineering Research 1988
S