I V 73(e

NBSIR 80-1636 FifCBPY

9 iff REM

SEP 9 - 196C LIQUEFIED NATURAL GAS RESEARCH

at the

NATIONAL BUREAU OF STANDARDS

PROGRESS REPORT FOR THE PERIOD

1 January - 30 June, 1980

THERMOPHYSICAL PROPERTIES DIVISION, NATIONAL ENGINEERING LABORATORY,

NATIONAL BUREAU OF STANDARDS, BOULDER, COLORADO

IMBSIR 80-1636

LIQUEFIED NATURAL GAS RESEARCH

at the

NATIONAL BUREAU OF STANDARDS

Thermophysical Properties Division

National Engineering Laboratory

National Bureau of Standards

Boulder, Colorado 80303

Progress Report for the Period

1 January - 30 June, 1980

°*CA\1

U.S. DEPARTMENT OF COMMERCE, Philip M. Klutznick, Secretary

Luther H. Hodges, Jr., Deputy Secretary

Jordan J. Baruch, Assistant Secretary for Productivity, Technology and Innovation

NATIONAL BUREAU OF STANDARDS, Ernest Ambler, Director
Prepared for:

American Gas Association, Inc.

1515 Wilson Boulevard

Arlington, Virginia 22209

Pipeline Research Committee

(American Gas Association, Inc.)

1515 Wilson Boulevard

Arlington, Virginia 22209

Gas Research Institute

10 West 35th Street

Chicago, Illinois 60616

U. S. Department of Commerce

Maritime Administration

Washington, DC 20235

U. S. Department of Commerce

National Bureau of Standards

National Engineering Laboratory

Boulder, Colorado 80303

U. S. Department of Commerce

National Bureau of Standards

Office of Standard Reference Data

Washington, DC 20234

LNG Custody Transfer Measurements Supervisory Committee

National Aeronautics and Space Administration

Lewis Research Center

Cleveland, Ohio 44135
ABSTRACT

The objective of this report is to:

1. provide all sponsoring agencies with a semiannual report on the

activities of their individual programs;

2. inform all sponsoring agencies on related research being conducted

at the NBS-NEL Themophysical Properties Division, NBS-NEL Mechanical

Processes Division and NBS-NML Fracture and Deformation Division;

3. provide a uniform reporting procedure which should maintain and

improve communication while minimizing the time, effort and

paperwork at the cost center level.

The work is supported by NBS and seven other agencies and represents the

collective expenditure of $646,000 during the 6 month reporting period. The

contents of this report augment quarterly progress meetings for certain of our sponsors and provide a perspective which is missing when the parts are viewed individually. Distribution of this document is limited and intended

primarily for the supporting agencies. Data or other information must be

considered preliminary, subject to change and unpublished, and therefore not

for citation in the open literature .

Key words: Cryogenics; liquefied natural gas; measurement; methane;

properties; research.

NOTICE

This LNG Semiannual Report has been compiled and distributed to over 150

sponsor designates every six months since 1972. Although the report still

identifies the composite research at NBS on LNG and related subjects, some basic programs have been completed and others have broadened research

activities into areas which are not strictly LNG related. We are, therefore,

considering the following actions as to the continuation of this reporting

procedure

1. Discontinue this report as of 1 January 1981. One additional report

would be issued in 1981 to cover this period progress.

2. Continue this report on LNG research but confine the contents to

only LNG research activities.

3. Broaden the scope of this report to include research on gases in

general, related material research and engineering measurements.

COMMENTS AS TO THE MOST DESIRABLE COURSE OF ACTION SHOULD BE DIRECTED TO:

Douglas Mann, Thermophysical Properties Division, Continuous Process

Technology Program, National Bureau of Standards, 325 Broadway, Boulder,

CO 80303.

i i i
CONTENTS

Cost Center

I. REFERENCE DATA

a) THERMOPHYSICAL PROPERTIES DATA FOR PURE 7730574, . . COMPONENTS AND MIXTURES OF LNG COMPONENTS 7732289

(Gas Research Institute; NASA Lewis Research

Center)

b) FLUID TRANSPORT PROPERTIES

(NBS-Office of Standard Reference Data)

7732290 . . 7732291

7730125

c) PROPERTIES OF CRYOGENIC FLUIDS (NBS

7730122 . . 7730124

7730125

7730424

d) PROPERTIES OF CRYOGENIC FLUID MIXTURES

(NBS; NBS-Office of Standard Reference

Data; Gas Research Institute)

7730123, . . 7732290,

7738574

e) MATERIALS FOR LNG APPLICATIONS (Gas

Research Institute)

7733574 . . 5621570

f) LNG MATERIALS RESEARCH, CONCRETES

(Maritime Administration)

7730403, . . 5621511

II. MEASUREMENT SCIENCE

a) CUSTODY TRANSFER - LNG SHIPS (Maritime

Administration; LNG Custody Transfer

Measurements Supervisory committee

7730460, . . 7731575,

7732575,

7733575,

7311573

b) LNG CUSTODY TRANSFER - LIQUID LEVEL

(Maritime Administration)

c) LARGE SCALE LNG MEASUREMENTS (Pipeline

Research Committee, AGA)

d) LNG DENSITY REFERENCE SYSTEM (Gas

Research Institute)

e) BASIC NATURAL GAS METERING (American Gas

Association, Inc.; Gas Research Institute)

7730460

7730570

7737574

7730571

7731571

III. TECHNOLOGY TRANSFER

a) LIQUEFIED NATURAL GAS TECHNOLOGY TRANSFER

(Maritime Administration; American Gas

Association, Inc.; Gas Research Institute;

NBS-Office of Standard Reference Data)

7730403, . . 7734574,

7738574,

7730594,

5621510

Page

1

4

6

11

14

17

20

21

22

24

26

38

IV
Title. THERMOPHYSICAL PROPERTIES DATA FOR PURE COMPONENTS AND MIXTURES

OF LNG COMPONENTS

Principal Investigators . R. D. Goodwin, H. M. Roder, G. C. Straty,

W. M. Haynes, R. D. McCarty, D. E. Diller, B. A. Younglove, and H. J. M.

Hanley

Cost Center Numbers . 7730574, 7732289

Sponsor Project Identification . Gas Research Institute Grant No.

5014-361-0131. National Aeronautics and Space Administration, Lewis

Research Center, Purchase Order C-78014-C.

Introduction Accurate phase equilibrium, equation of state (PVT) , and

thermodynamic properties data are needed to design and optimize gas

separation and liquefaction processes and equipment, and for mass and

heat transfer calculations. Accurate data for the pure components and

selected mixtures of hydrocarbon systems will permit developing

comprehensive accurate predictive calculation methods which take into

account the dependence of the thermophysical properties of mixtures on the composition, temperature, and density.

This project will provide comprehensive accurate thermophysical

properties data and predictive calculation methods for compressed and

liquefied hydrocarbon gases and their mixtures to support the

development of LNG technology at NBS and throughout the fuel gas

industry. It will also serve as the base for a comprehensive mixtures

prediction methodology.

Objectives or Goals . The objectives of our work are the determination

of comprehensive accurate thermophysical properties data and predictive

calculation methods for the major pure components (methane, ethane,

propane, butanes, and nitrogen) and selected mixtures of liquefied

natural gas and hydrocarbon mixtures at temperatures between 80 K and

320 K and at pressures up to 35 MPa (5000 psi). Our goal is to provide

a range and quality of data that will be recognized as definitive or standard for all foreseeable low temperature engineering calculations.

Background . Liquefied natural gas is expected to supply an increasing

percentage of the United States' future energy requirements. It is

likely that massive quantities of liquefied natural gas will be imported

during the years 1978 - 1990. Ships and importation terminals are being

built for transporting, storing, and vaporizing liquefied natural gas

for distribution. Accurate physical and thermodynamic properties data

for compressed and liquefied natural gas and hydrocarbon mixtures are needed to support these projects. For example, accurate compressibility

and thermodynamic properties data are needed to design and optimize

liquefaction and transport processes; accurate data for the heating

value, which for liquefied natural gas mixtures depends on the total

volume, the density, and the composition, are needed to provide a basis

for equitable custody transfer. Accurate mixture data prediction

methods are needed for use in automated heat transfer calculations.

Accurate thermodynamic properties data for liquefied gas mixtures must

be based on precise compressibility and calorimetric measurements;

compressibility data give the dependence of thermodynamic properties on pressure and density (at fixed temperatures); calorimetric data give the

dependence of thermodynamic properties on temperature (at fixed

pressures and densities). It is impossible, however, to perform enough

compressibility and calorimetric measurements directly on multicomponent

mixtures to permit accurate interpolation of the data to arbitrary

compositions, temperatures and pressures. Instead, thermodynamic

properties data for multicomponent mixtures must usually be predicted
(extrapolated) from a limited number of measurements on the pure

components and their binary mixtures. This project was initiated to

provide the natural gas and aerospace industries with comprehensive

accurate data for pure compressed and liquefied methane, the most

abundant component in LNG mixtures. We have published National Bureau

of Standards Technical Note 653, "Thermophysical Properties of Methane,

From 90 to 500 K at Pressures to 700 Bar," by Robert D. Goodwin (April

1974), and National Bureau of Standards Technical Note 684, "Thermophysical Properties of Ethane, From 90 to 600 K at Pressures to 700 Bar," by

Robert D. Goodwin, H. M. Roder, and G. C. Straty (August 1976). These

reports contain the most comprehensive and accurate tables available for

the thermophysical properties of pure gaseous and liquid methane and

ethane, and provide an accurate basis for calculating thermophysical

properties data for LNG and other hydrocarbon mixtures.

7. Program and Results .

7.1 Normal and Isobutane, Thermophysical Properties — R. D. Goodwin

Interagency reports have been printed, as follows:

NBSIR 79-1612, Isobutane: Provisional Thermodynamic Functions from

114 to 700 K at Pressures to 700 Bar, R. D. Goodwin, July, 1979.

NBSIR 79-1621, Normal Butane: Provisional Thermodynamic Functions

from 135 to 700 K at Pressures to 700 Bar, R. D. Goodwin, September

1979.

For each substance, PVT data are lacking at temperatures roughly below

the normal boiling point (NBP) but accurate densities for the saturated

liquid are available down to the triple point.

Specific heats for ideal gas states and for the saturated liquid below

the NBP were combined with the experimental heat of vaporization at the

NBP, and a virial equation to derive new data from the triple to the NBP

for saturated vapor densities, vapor pressures, and for heats of

vaporization

By use of these data with the highly-constrained, nonanalytic equation

of state, a thermodynamic network was derived for all fluid states at

temperatures above the triple point.

For propane and the two butanes new PVT data now are available (W. M.

Haynes) , including some other properties data such as vapor pressures

for propane. Work therefore is in progress to replace the NBSIR reports

on these fluids by revised work in NBS Technical Notes.

7.2 Sound Velocity of Propane — B. A. Younglove

All measurements are now complete. This includes sound velocity,

temperature, and pressure measurements on isotherms at 90, 100, 110,

120, 140, 160, 180, 200, 220, 240, 260, 280, and 300 K to a maximum

pressure of about 5000 psia (34.7 MPa). The isotherms extrapolate well

to the values measured at saturation which were mentioned in the

previous report. The results are now complete.

7.3

Calculational Methods -- R. D. McCarty and H. J. M. Hanley

Methods to calculate LLE and VLE via the technique of corresponding

states have been initiated.

8. Problem Areas. None.

2
9 . 1.0

Level of Effort . January 1 - June 30, 1980.

Staff-years expended

Equipment and/or Services Purchased

Approximate expenditures, total 80.0K$

10. Future Plans . Future plans are concerned with predicting and measuring phase

equilibria (LLE and VLE ) of the LNG systems.

3
1 . Title , FLUID TRANSPORT PROPERTIES

Principal Investigator . Howard J. M. Hanley

2. Cost Center Number . 7732290, 7730125, 7732291

3. Sponsor Project Identification . NBS-Office of Standard Reference Data

4. Introduct ion . Methods for predicting the transport properties of fluid

mixtures are unreliable and data are scarce. Prediction methods are needed, however, to supply the necessary design data needed to increase

efficiency and reduce costs.

5.

Objectives or Goals . The long range or continuing goal of the program

is to perform a systematic study of the theories and experimental

measurements relating to transport properties, specifically the

viscosity and thermal conductivity coefficients, of simple mixtures over

a wide range of experimental conditions. The specific objectives of the

program include: 1) the systematic correlation of the transport

properties of simple binary mixtures and the development of prediction

techniques, 2) development of a mixture theory for the dilute gas region

and the dense gas and liquid regions, 3) extension of the theory and

prediction techniques to multicomponent systems, and 4) investigation of

the properties and structure of fluids via computer similarities.

6 . Background . A continuing program has successfully expanded the stateof-the-art of transport phenomena for pure fluids. Information for pure

fluids is required as a prerequisite for mixture studies. The theory of

transport phenomena has been developed and applied to produce practical

numerical tables of the viscosity, thermal conductivity and diffusion

coef^yients

^ simple

^ | juids : Ar , Kr , Xe , N

2

, C> 2

, F

2

, He, H

2 , CH^ , C

2 Hg, C-jH q

. '3 8 It has been shown that a successful mixture program can emerge from

combining the results for pure fluids with mixture equation of state

studies. The equation of state work is being carried out by other

investigators in this laboratory.

7. Program and Results . A correlation of the transport properties of

ethylene is near the manuscript stage.'computer program to

predict the viscosity of mixtures suitable for a wide engineering

audience is near completion.

8. Problem Areas . The lack of suitable experimental mixture transport

properties data for comparison purposes remains a problem. Also

equation of state (PVT) data for mixtures are needed. Recent measure- ments on the methane-nitrogen system will help alleviate the problem.

(See 7.5 Thermophysical Properties Data for Pure Components and Mixtures

of LNG Components .

9.

Level of Effort . January 1 - June 30, 1980.

Staff-years expended

Equipment and/or Services Purchased

Approximate expenditures, total

0.5

21 .4K$

6 0 . 0K$

4
10. Future Plans . The theoretical transport program related to LNG is near completion. Future efforts will be directed towards mixtures of the

heavier hydrocarbons.

References

1. H. J. M. Hanley, Prediction of the Viscosity and Thermal Conductivity

Coefficients of Mixtures, Cryogenics, Vol 16, No. 11, 643-51 (Nov 1976);

H. J. M. Hanley, Prediction of the Thermal Conductivity of Fluid

Mixtures, Proceedings 7th ASME Conf. on Thermophysical Properties;

H. J. M. Hanley in "Phase Equilibria and Fluid Properties in the

Chemical Industry," ACS Symp. Series No. 60 (1977).

2. B. J. Ackerson and H. J. M. Hanley, J. Chem. Phys . (In press, 1980).

3. H. J. M. Hanley, W. M. Haynes and R. D. McCarty, The Viscosity and

Thermal Conductivity Coefficients for Dense Gaseous and Liquid Methane,

J. Phys. Chem. Ref. Data, Vol 6, No. 2, 597-609 (1977).

4. H. J. M. Hanley, K. E. Gubbins and S. Murad, A Correlation of the

Existing Viscosity and Thermal Conductivity Coefficients of Gaseous and

Liquid Ethane, J. Phys. Chem. Ref. Data, Vol 6, No. 4, 1167 (1977).

5. H. J. M. Hanley, P. M. Holland, K. E. Gubbins and J. M. Haile, J. Phys.

Chem. Ref. Data J3, 559 (1979).

5
1 . Title . PROPERTIES of cryogenic fluids

Principal Investigators . G. C. Straty, N. A. Olien, B. A. Younglove,

H. M. Roder, D. E. Diller, and J. F. Ely

2. Cost Center Numbers . 7730122, 7730124, 7730125, 7730424

3. Sponsor Project Identification . NBS , Department of Energy

4. Introduction . Accurate thermophysical properties data and predictive

calculation methods for cryogenic fluids are needed to support advanced

cryogenic technology projects. For example, liquefied natural gas is

expected to supply an increasing percentage of the United States' energy

requirements through 1990. Liquefaction plants, ships and receiving

terminals are being constructed to transport and store natural gas in

the liquid state ( LNG ) . Accurate thermophysical properties data for LNG are needed to design low temperature processes and equipment. Accurate

data will benefit the energy industries and the consumer by providing

for safe and efficient operations and reduced costs. We are now examining the data needs of a number of higher temperature industries

such as the synthetic natural gas (SNG) industry. This area of

technology as well as the liquefied petroleum gas (LPG) industry are logical extensions of the current LNG work. SNG mixtures can be

characterized as much more complex than natural gas, containing unlike

(including highly polar) molecules. Interactions between unlike

molecules are not well understood and the accurate data necessary to

quantitatively understand the interactions are lacking. The needs for

accurate predictive methods for SNG are essentially the same as LNG,

i.e., to reduce capital and operating costs and improve energy

ef f iciency

5. Objectives or Goals . The objectives of this project are to provide

comprehensive accurate thermodynamic, electromagnetic and transport

properties data and calculation methods for technically important

compressed and liquefied gases (helium, hydrogen, oxygen, nitrogen,

methane, ethane, etc.) at low temperatures. In addition we intend to

develop the capability to perform accurate PVT measurements on gaseous

mixtures and pure components at high pressures and above room temperature. Precise compressibility, calorimetric and other physical

property measurements will be performed to fill gaps and reconcile

inconsistencies. Definitive interpolation functions, computer programs

and tables will be prepared for engineering calculations. The immediate

goals of this work are to obtain accurate sound velocity and thermal

diffusivity data for compressed and liquefied gases by using laser light

scattering spectroscopy techniques; design, construct and performance

test a precision PVT apparatus for the region 250 - 900 K with pressures

to 35 MPa; and design, construct and performance test a transient

hot-wire thermal conductivity apparatus for the region 70 - 350 K with

pressures to 80 MPa.

6. Background . The application of laser light scattering techniques to

obtaining thermophysical properties data was initiated to complement and

check other measurement methods and to solve measurement problems

inherent in more conventional methods. For example, laser light

scattering techniques permit measurements of sound velocities for fluids

under conditions for which sound absorption is too large to perform

ultrasonic measurements; laser light scattering techniques permit

measurements of thermal dif f usivities under conditions for which

convection interferes with measurements of thermal conduction. The

feasibility of light scattering experiments to obtain data on binary

diffusion coefficients has also been demonstrated.

6
Light scattering allows thermal diffusivity measurements in the region

where density fluctuations are relatively large, but accuracy drops

significantly as you pass outside the extended critical region. To

complement the scattering method, thermal conductivity measurements can

be made with more conventional techniques such as a hot-wire technique.

In the latter method a very small platinum wire is surrounded by the

fluid and a voltage pulse is applied to the wire. The temperature of

the wire is momentarily raised and the resistance increases. A series

of very closely spaced resistance measurements would describe the return

of the wire to equilibrium. These resistance vs. time measurements can

be related to the rate of heat dissipation in the surrounding fluid and

thus the thermal conductivity (provided convection heat transfer is

prevented )

.

The development of accurate mathematical models (equation of state) for

fluid mixtures requires accurate PVT data for the pure constituents and

binary mixtures of key molecular pairs. Experience with LNG has

identified the type and accuracy of the data required. In addition to

that, work on SNG at high temperatures is a logical follow-on to the low

temperature work on LNG. Typical constituents of raw SNG from coal via

the Lurgi process are: water - 50.2%; hydrogen - 20.1%; carbon

dioxide - 14.7%; carbon monoxide - 9.2%; methane - 4.7%; ethane - 0.5%;

hydrogen sulfide and others - 0.6%.

An apparatus has been assembled for laser light scattering spectroscopy

measurements on compressed and liquefied gases (76 - 300 K, 35 MPa).

The apparatus consists of a high pressure optical cell, a cryostat

refrigerated by means of liquid nitrogen, an argon ion laser and

low-level light detection equipment.

The light scattered from fluctuations in the fluid can be analyzed with

either digital autocorrelation techniques for the examination of the

very narrow lines associated with scattering from temperature

fluctuations (Rayleigh scattering) or with a scanned Fabry Perot

interferometer for the measurement of the Doppler frequency shifts

associated with the scattering from propagating density (pressure)

fluctuations (Brillouin scattering).

Apparatus for photon-counting and digital autocorrelation has been

assembled, interfaced with computer facilities and programmed to enable

on-line data accumulation and analysis. Initial problems associated

with signal modulations from excessive building vibrations have been

solved by levitating the apparatus on an air suspension system. A

small, highly stable capacitor has also been designed, constructed and

installed inside the scattering cell to permit the dielectric constant

of the scattering fluid to be determined, which should allow more accurate fluid densities to be obtained for use in the data analysis.

Apparatus tests on well characterized, strongly scattering, test fluids

have been made to verify data analysis programs.

7 . Program and Results . 7.1 Transient Hot-Wire Apparatus - H. M. Roder. Measurements

Measurements of the thermal conductivity of oxygen on isotherms of 77,

99, 122, 145, 160, 180, 202, 218, 241, 264, 282, 296, and 308 K are complete

.

7
Data Distribution.

Oxygen measurements

cell alinement

reproducibility, accuracy, precision checks

points requiring additional analysis

"isotherms", points plotted in graph 1

162

151

90

1387

Helium measurements

"isotherm," 307 K 78

Total 1868

Plot . A point plot of 1387 conductivity measurements is given in

graph 1. Nominal isotherm temperatures (+ 2 K) are indicated on the

graph. Surprisingly, the influence of the critical point is clearly

evident, even though the apparatus supposedly is not capable of

measuring in the near critical regime. A comparison with calculated

thermal conductivities, NASA SP-3071, yields systematic differences

between experimental measurements and the correlation. Deviations are 5 to 20% at the very lowest densities and 15 to 25% at the very highest

densities, with most isotherms reaching a zero departure at some intermediate density.

Future . Additional analysis is still required on the points below the

vapor pressure curve, on points on the 160 K isotherm for densities less

than critical, and for all isotherms at densities below 1 mol/L for

pressures less than about 4 bars where the influence of the outer wall

on the experiment is likely. After that preparation of a final report

will be undertaken.

1.2 Laser Light Scattering Measurements . This project is inactive at

the present time.

7.3 High Temperature PVT Apparatus - G. C. Straty and B. A. Younglove.

Funding for this program was obtained in December 1978. Nearly all of

the required equipment for the new PVT apparatus has now been

constructed or acquired and the apparatus is being assembled. Initial

temperature run-up and apparatus check out have been made followed by some preliminary measurements, probably on methane. The completed

apparatus will be a semi-automated PVT data acquisition system for

measurements to pressures of 35 MPa at temperatures from room temperature to about 1000 K. This will complement existing PVT

facilities used for measurement below room temperature.

7.4 Mixture Composition Determination Using Raman Spectroscopy - D. E. Diller. A joint project on in-situ mixture composition determination

was carried out while Diller was on an exchange visit with NML, NBS

Gaithersburg during October 1978 - June 1979. The feasibility of using

Raman spectrometry for determining the composition of mixtures of

natural gas components was examined. Raman intensity measurements were carried out on eight, gravimetr ically prepared, binary gas mixtures

containing methane, nitrogen and isobutane at ambient temperature and at

pressures to 0.8 MPa. The repeatability of the molar intensity ratio,

(

2 /y 2

) /I ]_/y 1) f where y-j_ is the concentration of component 1 in the

mixture, and I ^ is the intensity of the related line in the mixture

spectrum, was examined. The compositions of two gravimetr ically

prepared methane-nitrogen-isobutane gas mixtures were determined

spectrometr ically with an estimated precision of about 0.001 in the mole

fraction. Typical differences from the gravimetric concentrations were

less than 0.002 in the mole fraction. The Raman spectrum of a gravimetrically prepared, eight component, hydrocarbon gas mixture was obtained to show that the Raman spectrometr ic method has potential for

being applicable to natural gas type mixtures.

8
A manuscript entitled "Composition of Mixtures of Natural Gas Components

Determined by Raman Spectroscopy" by D. E. Diller and R, F. Chang has

been accepted for publication by Applied Spectroscopy.

Equipment is being assembled to continue this work in Boulder. The

method has potential for studying multiphase, multicomponent equilibria

at extreme conditions and near the critical point of a mixture.

7.5 Methane, Viscosity Measurements - D. E. Diller. The dependence of

the shear viscosity coefficient of compressed gaseous and liquid methane

on temperature, pressure and density has been determined at nine

temperatures between 100 K and 300 K and at pressures up to about 30 MPa

with a torsionally oscillating quartz crystal viscometer. The estimated

imprecision and inaccuracy of the measurements are about 0.5% and 2%

respectively. The measurements have been compared with an equation

previously proposed (J. Phys . Chem. Ref. Data 6, 597 (1977)) for

calculating the viscosity of compressed gaseous and liquid methane.

Most of the differences between the equation and the measurements are within our experimental error. Significant differences between the

measurements and the equation are reported only at the lowest

temperature and highest pressures (100 K, _< 30 MPa), and along a supercritical isotherm at 200 K (T ~ 1.05 Tc

).

A manuscript entitled "Measurements of the Viscosity of Compressed

Gaseous and Liquid Methane" has been submitted to Physica (Leiden) for

publication.

7.6 Ethane, Viscosity Measurements — D. E. Diller. Measurements of

the shear viscosity coefficient of compressed gaseous and liquid ethane

(95-320 K, 30 MPa) are in progress. Measurements along the saturated

liquid curve (95-300 K) and along isotherms at 290, 250, 200, 150, 120

and 100 K have been completed. The measurements are being compared with

an equation previously proposed (J. Phys. Chem. Ref. Data 6, 1167

(1977)) for calculating the viscosity of compressed gaseous and liquid

ethane. The differences between measured and calculated viscosities are

less than 6%.

Measurements along isotherms at additional temperatures are planned for

completion during the next quarter.

7.7 Prediction of Thermophysical Properties of Mixtures - J. F. Ely.

Efforts are underway to develop accurate methods of predicting

thermophysical properties of mixtures containing polar and non-polar

components. Currently, a general computer program for predicting phase

equilibria is being developed and tested for simple equation of state

models. When fully developed, this program will be used to explore a modified extended corresponding states model and the Leung-Grif f iths

model for phase equilibria and other thermophysical properties.

Problem Areas . None.

Level of Effort . January 1 - June 30, 1980

Staff-years expended

Equipment and/or Services Purchased

Approximate expenditures, total

2.5

21 .0K$

180. 0K$
10. Future Plans.

Quarter

Objectives and Schedule: 3 | 4 Complete experimental data on thermal

conductivity of oxygen

Design, construct and performance test high

temperature-high pressure PVT apparatus.

Measure, analyze and report viscosity data

for ethane in compressed liquid and

gas region.

Complete computer program for predicting

mixture phase equilibrium.

Develop accurate model for thermophysical

properties of polar-nonpolar mixtures.

10
1 . Title. PROPERTIES OF CRYOGENIC FLUID MIXTURES

Principal Investigators . M. J. Hiza, A. J. Kidnay (part-time), R. C.

Miller (part-time), and E. D. Sloan (part-time)

2. Cost Center Numbers . 7730123, 7732290

3. Sponsor Project Identification . NBS , NBS (OSRD) , Gas Research Institute

grant No. 5014-361-0131

4. Introduction . Accurate thermodynamic properties data and prediction

methods for mixtures of cryogenic fluids are needed to design and

optimize low temperature processes and equipment. This project provides

new experimental measurements on equilibrium properties and compilations

of evaluated equilibrium properties data which are suitable for direct

technological use or for the evaluation of prediction methods.

5. Objectives or Goals . The overall objectives of this project are to

provide critically evaluated data on the phase equilibria and thermodynamic properties of cryogenic fluid mixtures. The program has been

divided into the following elements:

a) Preparation of a comprehensive bibliography on experimental

measurements of equilibrium properties for mixtures of selected

molecular species of principal interest in cryogenic technology.

b) Selection and/or development of methods for correlation, evaluation

and prediction of equilibrium properties data.

c) Retrieval and evaluation of experimental data for specific mixture

systems selected on the basis of theoretical and/or technological

importance

.

d) Preparation of guidelines for future research based on the

deficiencies noted in (a), ( b ) , and (c).

e) Performing experimental research to alleviate deficiencies and

provide a basis for improvement of prediction methods.

6. Background . A physical equilibria of mixtures research project was established in the Thermophysical Properties Division in 1959. The

initial effort, based on a bibliographic search and other considerations, was directed toward the acquisition of new experimental data on

the solid-vapor and liquid-vapor equilibria and physical adsorption

properties for a limited number of binary and ternary mixtures of

components with widely separated critical temperatures. Most of the

systems studied included one of the light hydrocarbon species —

methane, ethane, or ethylene (ethene) — with one of the quantum

gases -- helium, hydrogen, or neon. The data for these systems led to

significant improvements in the predictions of physical adsorption

equilibrium and a correlation for the prediction of deviations from the

geometric mean rule for combining characteristic energy parameters. In

addition, significant new information was obtained for interaction third

virial coefficients which was used in a correlation by one of our consultants, J. M. Prausnitz. The approach taken in this work has been

as fundamental as possible with the intention of having an impact on a broad range of mixture problems.

Recent efforts have been directed toward problems associated with

systems containing components with overlapping liquid temperature

ranges, such as nitrogen + methane, methane + ethane, etc.

11
7. Program and Results . A summary of recent progress is as follows:

a) The paper discussing compilation, evaluation, and correlation of

liquid-vapor equilibria data for methane + propane^

1

' is in press

in the Journal of Physical and Chemical Reference Data.

b) A paper on experimental phase equilibria measurements principally

explor

ethene

Equilibria. Included are some measurements on the nitrogen + ethane system. This paper is in editorial review.

ng the liquid-liquid-vapor equilibrium region for nitrogen

' ’ has been prepared for the journal Fluid Phase

+

c) The systematic effort to reexamine consistency tests for phase

equilibria data, and criteria for evaluating PVTx in general, has

been pursued at a low level of effort this past semester, but will

be more active the latter part of this year. Testing of data over

all PVTx space for nitrogen + methane is the goal.

d) The updated and expanded version of the bibliography^^ has been

typed. We are now in the process of sorting, integrating, proofreading and revising the final product to prepare a copy for

review, probably to start in the third quarter.

8. Problem Areas . None

9. Level of Effort . January 1 - June 30, 1980

Staff-years expended

Equipment and/or Services Purchased

Approximate expenditures, total

10. Future Plans . Objectives and Schedule:

Complete proofreading and revisions of

updated and expanded bibliography,

initial review.

Prepare final draft of paper on liquidliquid-vapor for nitrogen + ethene

and nitrogen + ethane for submission

to Fluid Phase Equilibria.

Continue systematic study of consistency

tests. Begin analysis of available

phase equilibria and PVTx data for

nitrogen + methane.

References

0.8

15 . 0K$

75 . 0 K$

Quarter

3 I 1

1. R. C. Miller, A. J. Kidnay, and M. J. Hiza, A Review, Evaluation, and

Correlation of the Phase Equilibria, Heat of Mixing, and Change in

Volume on Mixing for Liquid Mixtures of Methane + Propane, J. Phys.

Chem. Ref. Data (in press).

2. K. A. Massoud Gasem, M. J. Hiza, and A. J. Kidnay, Phase Behavior in the

Nitrogen + Ethylene System from 120 to 200 K, prepared for Fluid Phase

Equilibria (in review for BERB).

12
3. M. J. Hiza, A. J. Kidnay, and R. C. Miller, Equilibrium Properties of

Fluid Mixtures - A Bibliography of Data on Fluids of Cryogenic Interest,

NSRDS Bibliographic Series, IFI/Plenum, New York, 1975.

13
1 . Title. MATERIALS FOR LNG APPLICATIONS

Principal Investigators . L. L. Sparks, and J. M. Arvidson

2. Cost Center Number . 7733574, 5621570

3. Sponsor Project Identification. Gas Research Institute Grant Number

5014-361-0131.

4. Introduction . Safe, economical storage and transportation of LNG

depend to a large extend on the materials used in the construction of

capital equipment, i.e., ships, storage facilities, transfer terminals,

liquefiers, and pipelines. Thermal insulations constitute a critical

link in the materials for use in LNG oriented energy efforts because of

the cryogenic nature of the liquid.

Expanded plastics (foams) are being used or are being considered for use

in facilities such as these. Low-temperature properties data,

standardized low temperature test methods, and standard reference

materials are not presently adequate to meet the needs of complicated

insulation systems. These materials are anisotropic for most properties

so that properties data must be accompanied by specimen characterization

in order to be of general use. Standard reference materials, for use in

checking experimental systems are completely lacking. With the

exception of thermal conductivity, standardized test methods for

low-temperature testing of foams are also completely lacking.

5. Objectives or Goals . The broad objectives of this project are twofold:

first, provide the users of thermally insulating foams with basic knowledge about the behavior of expanded plastics at cryogenic temperatures

and methodology to allow safe, economical use of specific materials;

second, serve as a center of insulation material information for GRI and

associated users of cryogenic fuels. The first objective will be

achieved by determining the low-temperature thermal and mechanical

properties of selected, well characterized foams. The methodology of

testing at low temperatures and characterizing the test materials will

be stressed. The second objective will result as a consequence of this

research effort.

6. Background . The Thermophysical Properties Division has been involved in

the development and application of thermal insulations since being

established in 1951.

The Properties of Solids group at Boulder has successfully examined the

thermal and mechanical properties of a wide variety of materials:

metals, polymers, insulations, and composites. The group, as a whole,

has the equipment and expertise to establish and perform low temperature

tests to determine the mechanical and thermal properties of foams.

Close working relationships with private companies, universities, and

professional associations provide guidance in the areas of material

selection, quality control, and standardization of materials and

methods

The groundwork for the current foams research was done while working on the Insulation Section of the LNG Materials Handbook (funded by Maritime

Administration)

7. Program and Results . The program designed to meet the need for

data and standards for expanded plastics includes the following items:

assessment of materials, assessment of methods, specimen acquisition,

specimen characterization, and testing. A continuing survey of the

literature and contacts with many foam related companies are being used

to assess materials and methods.

14
The cooperation of users, producers, standardization societies, and

other government labs, is extremely important to the success of the

program. It is being stressed, particularly with the producers, that

this program is not intended to do their research for them; our results

will be related to identifiable characteristics such as general type of

foam, cell size, membrane thickness, manufacturing process, etc.

Property dependence on these parameters can be related to new as well as existing products. Cooperation with users of foam insulations benefits

the program by increasing our knowledge of practical, field-type

problems

.

All program areas mentioned above (assessment of materials and methods,

specimen acquisition, specimen characterization, and testing) have shown

progress during this reporting period:

Assessment of materials and specimen acquisition. The material to be

tested in the initial tests was selected and acquired in the previous

reporting period. Additional specific information on this material is

being sought from the producer, in addition to the NBS characterization

discussed below. Material (polyurethane foam) from a commercial LNG

ship tanker has also been obtained and is being characterized. The

cooperation of several commercial foam producers has been assured and

will allow us to obtain materials on request. Since many of the

properties in question are somewhat time dependent, specimens will not

be stockpiled, but rather obtained as near to the time of use as practical.

Test Methods. All procedures for mechanical and thermal testing have

been outlined. These procedures are continuously evaluated and refined

as our experience with new experimental systems accumulates. Thermal

contraction of large inhomogeneous specimens will be accomplished

utilizing a recently completed system designed for this purpose. This

system includes an environmentally controllable test space. The

mechanical properties will be determined in a recently completed system

which utilizes capacitance gauge techniques. This system also allows a controlled test environment. Initial tests on both the thermal

contraction and mechanical properties systems indicate that extremely

precise and accurate measurements will be possible.

Specimen Characterization. This area has again been emphasized during

this period. Optical methods of characterization have continued;

Statistical methods are being used to evaluate reproducibility and

observer influence. Preparations are being made to add scanning

electron microscopy to the list of optical methods of evaluation.

Differential thermal analysis (DTA) techniques were used to study

several foams including the LNG ship foam and the initial material

chosen for testing here. These tests were performed at NASA-Marshall

Space Flight Center (MSFC) in Hunstville, Alabama. Although the data

analysis is not yet complete, the preliminary results indicate that this

test may be extremely useful in comparing the chemical makeup of foams.

Testing. Testing during this reporting period is of a preliminary

nature and was done to evaluate various apparatus functions.

Problem Areas . None.

Level of Effort . January 1 - June 30, 1980

Staff-years expended

Equipment and/or Services Purchased

Approximate expenditures, total

0.57

$ 6,020

$31,180
10. Future Plans . During the next reporting period we will complete the

thermal and mechanical testing programs for the material now being

considered. We will continue to refine our cellular study techniques

and our analysis capability. A crucial phase of the program, relating

observed cryogenic properties to foam structure, chemistry, and

processes, will begin. Our cooperation with other government agencies

and industrial users of foams will continue and expand as relevant

opportunities come to our attention. In particular, differential

scanning calorimetry will be fruther evaluated as a possible tool; this

work will be done at NASA-MSFC by NBS personnel.

16
1 . Title. |_NG MATERIALS RESEARCH, CONCRETES

Principal Investigators . L. L. Sparks and J. M. Arvidson

Cost Center Number. 7730403, 5621511

3. Sponsor Project Identification . Maritime Administration, Miscellaneous

Purchasing Order No. 400-89019.

4. Introduction . Concretes are attractive materials for construction of

large LNG installations because of lower material cost and economies of

fabrications compared to alternative construction methods. They exhibit

favorable mechanical and thermal properties for use in LNG applications.

Although these materials are presently used to some extent in LNG

construction, lack of confidence in their cryogenic behavior has

restricted their use to noncritical components or has resulted in overly

conservative and expensive designs. This reflects the lack of

dependable cryogenic thermal and mechanical properties data and a poor

understanding of the effect of field fabrication variables on cryogenic

performance

.

Applications of special concretes such as lightweight, cellular, fiber

reinforced, and polymer will depend on their cryogenic properties, which

are unknown at this time. The experimental program to determine these

properties will be executed in cooperation with the USCG, Portland

Cement Association (PCA), and several private corporations.

5. Objectives or Goals . The program objectives are to determine the

properties (76 K £ T _< 300 K) of concretes which are presently being

used in LNG applications and those which may provide design alternatives

in the future. The properties which may be determined include: thermal

conductivity, Young's modulus, thermal expansion, compressive strength,

fatigue strength, splitting strength, permeability to water and LNG, and

thermal shock. The dependence of these properties on parameters such as moisture content, air content, water- to-cement ratio, additives,

aggregate type and grade, and aging will be determined. The parameter

dependencies will be studied in order to understand the fundamental

basis for the cause/effect relationships which are observed. Specimen

characterization and parameter control are extremely important to this

phase of the program. Knowledge gained from the parameter dependencies

will be used to assess variabilities found in field-erected structures.

This information is needed to establish the quality control necessary to assure f itness-for-service in cryogenic applications. The testing

procedures which are used must produce reproducible and accurate data.

With the exception of thermal conductivity tests, there are no standardized procedures for testing concretes at low temperatures. The large

variations found in the literature are due, in part, to this deficiency.

Whenever possible, ASTM , and ACI procedures, modified to accommodate the

extreme environment, will be used throughout this program.

6. Background . The ini

Division in the use was in 1973. Safety

tions were stressed,

in these safety eval

low- temperature data

low-temperature expe

has not changed sign

tial involvement of the Thermophysical Properties

of concretes as low temperature structural materials

aspects of concrete, in low-temperature installaData from the literature were collected and used

uations; it became very clear that reliable

, basic cause/effect relationships, and standardized

rimental procedures were inadequate. The situation

if icantly

.

17
7. Program and Results . The long-range objective for the program is to

establish an understanding of the behavior of concrete in the

temperature range above 76 K. This understanding or model will be based

on and tested by state of the art measurements on two "ordinary"

concrete mixes (portand cement, sand and gravel aggregates). The

effects of parameters such as moisture and air content, water to cement

ratio, additives, aggregate type and size, and age will be determined.

Properties to be used in this study include thermal conductivity and

contraction, and the strengths and moduli. Field poured concrete and

alternative types of concrete will be studied using the procedures and

basic knowledge gained from the ordinary concrete tests and analysis.

The initial compressive tests exhibited an unexpected degree of scatter

in both the strength and moduli, particularly at 76 K. The primary

effort for this reporting period (funding was not available until

28 April 1980) has been to reevaluate testing procedures and specimen

composition in an effort to reduce the observed scatter. We are developing the capability to make specimens at NBS (the initial set of

specimens was purchased from a non-NBS laboratory). This will allow

tighter control on specimen composition and aging. The facility for

aging (specified in ASTM C192) has been completed. Portland cement,

type I, has been acquired along with a detailed chemical analysis of the

cement (as specified in ASTM C150). Petrographic analysis of the

locally acquired aggregate is in progress as is the chemical analysis of

admixtures to be used in the concrete specimens.

8. Problem Areas . None.

9. Level of Effort . January 1 - June 30, 1980

Staff-years expended 0.1

Equipment and/or Services Purchased $ 4,547

Approximate expenditures, total $11,263

10. Future Plans . Thermal and mechanical properties of the well characterized concrete mix, tested in compression in the 1979 program, will be

completed in the temperature range 76 _< T £ 300 K. The specific

properties which remain to be determined are thermal conductivity,

thermal contraction (AL/L), flexural strength, and splitting strength.

These properties plus compressive strength will also be determined for a second, different concrete mix. This testing program involves a large

number of individual tests, since multiple (a minimum of three)

specimens are required at each temperature for each test. Knowledge of

specimen variability obtained from these multiple tests is an essential

part of the basic property data for concrete specimens.

The apparatus to be used in determining AL/L for large, inhomogeneous

specimens such as concrete has been completed, and is now being

calibrated. Preliminary testing and evaluation will be completed in the

next reporting period along with data on concrete. In view of the lack

of reliable data for this important design property, these measurements

will be stressed; it is tentatively planned to study this property for

other concretes in addition to the two mixes discussed above.

Characterization of specimens, which includes obtaining detailed

information of moisture content, aggregate type and distribution, air

content, porosity, and chemical composition of the cement, are required

for each type of specimen. We will continue to develop and refine our capability to make, characterize, and test concrete specimens in the

temperature range T > 76.

18
In addition to producing much needed low-temperature data for concrete,

the 1980-81 program will provide the groundwork for the very important

parameter variability study anticipated in 1981-82. Established test

method and characterization procedures are prerequisites for determining

effects of parameters such as aggregate variability, moisture content,

air content, void density, and cement composition on the thermal and

mechanical properties. The results of the 1980-81 effort will be

published in the open literature, reported to the sponsor in technical

reports, and presented at appropriate technical meetings.

19
1 . Title . CMSTOny TRANSFER - INF SHIPS

Principal Investigators . W. C. Haight, R. J. Hocken, B. R. Borchardt,

R. G. Hartsock, R. C. Veale, J. D. Siegwarth, J. F. LaBrecque, C. L.

Carroll, C. P. Reeve, and F. E. Scire

2. Cost Center Numbers . 7730460, 7731575, 7732575, 7733575, 7311573,

7311577

3. Sponsor Project Identification . LNG Custody Transfer Measurements

Supervisory Committee and Maritime Administration Misc. P. 0.

#400-79005.

4. Introduction . In response to the requests from the U.S. shipbuilding

industry, NBS is independently examining the accuracies of LNG tank

cargo capacity tables and developing alternative survey techniques.

5. Objectives . The objectives of the program are to develop new techniques for LNG transport tank calibration and to test the accuracy

of present calibration techniques as part of an overall study of

custody transfer methods aimed at increasing the accuracy of custody

transfer meansurements

6. Background . Initial funding by the Maritime Administration (7730460)

supported some preliminary tests of calibrations of spherical LNG ship

tanks. As a result of these measurements, the LNG Custody Transfer

Supervisory Committee and the Maritime Administration have funded

extension of the work to the membrane tanks and the free standing

prismatic tanks now under construction in U.S. shipyards.

7. Program . The calibration reports have been completed and issued for

all three of the membrane ships. The NBS determined volume height

relationships for these tanks agree with those determined by the

primary surveyor to better than + 0.2%.

Interim reports of analyses of the three photogrammetric surveys are completed for the ships employing the free standing prismatic tank

design. The volume determined by the primary survey agrees with the

independent determination by NBS to better than + 0.2%.

8. Problem Areas . Completion of this work has been delayed because of

problems with the tank insulation system.

9. Level of Effort . January 1 - June 30, 1980

Staff years expended .1

Approximate expenditures, total 8K$

10. Future Plans . The results of other measurements related to tank

calibration accuracy will be reported. These various reports will be

combined into a final report estimating the calibration accuracy of the

cargo tanks of these three ships.

20
1. Title. |_NG CUSTODY TRANSFER - LIOUID LEVEL

Principle Investigators . J. D. Siegwarth

2. Cost Center Number . 7730460

3. Sponsor Project Identification . Maritime Administration

4. Introduction . Except for liquid level, the National Bureau of Standards

has examined the accuracy of all the measurements required to establish

cargo value in the LNG trade. Density, composition, and volume

determination techniques as well as models relating density to

composition and temperature have been examined and the measurement

accuracy estimated.

5. Objective . By examining the level gauge design, calibration and

performance under operating conditions as well as intercomparing gauges

on the same tanks when possible, we will estimate gauge accuracies.

6. Program . We are collecting manufacturer's information and papers from

the open literature on the various gauging systems and methods.

7. Problem Areas . Possible delays due to shutdown in the major import

operation to United States.

8. Level of Effort . January 1 - June 30, 1980

Staff years expended 0.1

Approximate expenditures 4K$

9. Future Plans . We will complete our collection of published information.

We will make the necessary arrangements to visit manufacturing

facilities to observe gauge calibrations and visit those firms. From

these visits we should obtain some knowledge of repeatability and

accuracy under laboratory conditions. Coincidentally, we will arrange

to visit sites where the level gauges are in use and observe gauging

operations under actual field conditions. From such observations, we should be able to obtain qualitative estimates of the repeatability and

resolution under actual service conditions.

21
Tit le , large SCALE lng measurements

Principal Investigators . J. A. Brennan

Cost Center Number . 7730570

Sponsor Project Identification . Pipeline Research Committee (American

Gas Association) PR-50-104.

I ntroduct ion . This project will investigate the scaling of a vortex

shedding flowmeter from 12 inch (30 cm) to 32 inch (81 cm) diameter.

The method used for testing the scale-up will be comparisons to storage

tank volumes. Liquid level measurement in and volume determination of

large storage tanks will be an important element in this investigation.

Also included within this project will be work on LNG densimetry in

pipeline applications and LNG flow measurement using ultrasonic

flowmeters

Objectives and Goals . The major objectives of this project are to

extend flowmeter scaling to larger pipe diameters, to evaluate LNG

densimetry under actual end use conditions and begin liquid level

evaluation in large land based tanks. The work will be completed at a new LNG import terminal now under construction.

Background . Previous work on LNG flow element investigations was

limited to a maximum line size of 12 inch (30 cm). The work was completed utilizing industrial LNG peakshaving and import facilities and was related back to the NBS cryogenic flow facilities in Boulder,

Colorado, and the NBS water flow facilities in Gaithersburg, Maryland.

Extensive densimeter evaluations have also been completed at NBS-Boulder

with some additional testing at an LNG import terminal. This project

will extend the previous work to larger line sizes and also start work

on liquid level measurements in large storage tanks.

Program and Results . The new recording instrumentation referred to in

the last report has been received. Some initial checkout and

familiarization tests have been completed. The complete checkout at

Southern Energy Company's import terminal cannot be performed until LNG

imports are resumed.

LNG storage tank volumes at the Trunkline import terminal are being

measured by a commercial firm under a separate contract using photogrammetric techniques. Some redundant scale tapes will be provided by NBS

to provide an independent check on the volume vs. height determinations.

These tank measurements are critical to the flowmeter tests since they

will provide the reference values for the flowmeter comparisons.

Problem Areas . The selection of an ultrasonic flowmeter has been

delayed because of the requirement to have retractable transmitters. Of

the flowmeters available with demonstrated cryogenic performance none has been found with the retraction capability. The necessary mounting

flanges are being included on the pipeline so that the flowmeter can be

installed when the problem is solved.

Level of Effort . January 1 - June 30, 1980

Staff years expended

Equipment and/or Services Purchased

Approximate expenditures, total

.2

31K$

40K$
10. Future Plans . NBS will provide scale tapes for the photogrammetric

survey of the first LNG storage tank. This survey is scheduled for

mid-July. Check procedures on future tanks will depend on the results

obtained on the first tank.

Instrumentation checkout tests will be scheduled when LNG becomes

available again.

23
1. Title , lmg DENSITY REFERENCE SYSTEM

Principal Investigators . J. D. Siegwarth and J. F. LaBrecque

2. Cost Center Number . 7737574

3. Sponsor Project Identification . Gas Research Institute, Grant No.

5014-361-0131.

4. Introduction . A density reference system has been developed to evaluate

the ability of commercially available instruments to measure densities

of LNG directly. Density is an essential measurement in determining the

total energy content of natural gas reservoirs.

5. Objectives . The object of this research is to develop and supply

adequate calibration methods and calibration standards to densimeter

manufacturers and users for providing traceability of accuracy to field

density measurement systems.

6. Background . The density reference system project was initiated in 1973.

Since that time the reference system has been designed, constructed, and

is now in operation, evaluating commercial density metering systems.

Reports describing the density reference system and the results of the

tests of four commercial densimeters have been published. These reports

are:

Siegwarth, J. D. , Younglove, B. A., and LaBrecque, J. F. , Cryogenic

fluids density reference system: provisional accuracy statement,

National Bureau of Standards (U.S.) Technical Note 698, 24 pages (1977),

and

Siegwarth, J. D. , Younglove, B. A., and LaBrecque, J. F. , An evaluation

of commercial densimeters for use in LNG, National Bureau of Standards.

(U.S.) Technical Note 697, 43 pages (1977).

The work has also been presented in the following papers:

Siegwarth, J. D., Younglove, B. A., and LaBrecque, J. F. , Test of

densimeters for use in custody transfer of LNG, Proc 53rd International

School of Hydrocarbon Measurement, Normon, Oklahoma (1978).

Parrish, W. R. , Brennan, J. A., and Siegwarth, J. D., LNG custody

transfer research at National Bureau of Standards, American Gas

Association Operating Section Proc. T243 (1978).

7. Program . The Portable Density Standard (PDS) has been completed and

compared to the DRS densimeter in the DRS . The densities measured by

the two instruments are indistinguishable since the difference is well

under 0.01%.

An updated accuracy statement for the DRS is nearing completion. A

report of the results of the comparison between the DRS and PRD is in

preparation

The third vibrating element densimeter for a calibration transfer

standard was tested in two fillings and returned for repair since a leak was causing an instability in the resonant frequency.

The work on a second report of measurements on commercial densimeters

has started but is not planned for completion until the third vibrating

element densimeter has been returned for testing.

8. Problem Areas. None.

24
9. Level of Effort . January 1 - June 30 f 1980

Staff-years expended

Equipment and/or Services Purchased

Approximate expenditures, total

1/3

$ 5,000

$28,000

10. Future Plans . The DRS update and the Portable Density Standard reports

will be completed next period. The report of the further studies of

commercial densimeters should be nearly complete. The third vibrating

element densimeter calibrations should be completed by then and included

in that report. The comparisons of the DRS and the Gaz de France

densimeter calibration facilities via the portable reference densimeter

is still in the planning stage.

25
1 . Title . RASIC NATURAL GAS METERING

Principal Investigators . Douglas Mann, James A. Brennan, Charles E. Sindt, and Clarence Kneebone

2. Cost Center Number . 7730571, 7732571, 7731571

3. Sponsor Project Identification . Gas Research Institute Research Grant

No. 5014-361-0131 and American Gas Association, Inc.

4. Introduction . The National Bureau of Standards has under development a gas flow reference system capable of directly relating gas meter

peformance to standards of mass and time. The facility coupled with

existing liquid flow capabilities will provide a basis for significant

improvements in gas quality and quantity measurements.

The new system will provide a factor of five to ten improvement in the

total uncertainty of gas flow measurement which may be applied immediately to gas industry developed standards and codes. This could reduce

the bias within field meters of the same generic type and size or meters

of different types. The benefits are two fold; possible reduction in

unaccounted for gas and increased credibility of measurement.

Reporting progress of this project under the NBS LNG Research program

is justified by the general interst of the natural gas industry in both

liquid and gas measurement research and a direct relationship of natural

gas flow measurements to LNG flow measurements. Specifically, the

project HEATING VALUE OF FLOWING LNG (see table of contents) relies

heavily on the measurements of vaporized LNG (natural gas) to establish

accuracy and precision of the LNG flow metering.

5. Objectives and Goals . The objectives of the program are to apply the

capabilities of the new gas flow reference system to an existing well

characterized gas industry measurement problem to assess the value of

the new system in significantly improving gas flow measurements. If

successful, the program will be directed to Improving gas flow

measurement through upgraded existing codes and the development of

necessary data for defining new model codes and standards for gas flow

measurement

6. Background . Natural gas is collected, transported and distributed to

industries, residences and utilities through one million miles of

pipelines and mains. Ownership changes many times as the gas is

delivered from the producer to the consumer and at each change of

ownership, the value is established by some type of measurement. The

establishment of value of natural gas in commerce as to both quantity

and quality is usually made under dynamic flow conditions.

Measurement of value is accomplished using many different types of

instruments such as positive displacement meters for small residential

users to large head type or turbine type meters in transmission lines.

Establishment and maintenance of the measurement system is a vital

element of interest to both the gas industry and the National Bureau of

Standards

Calibration or proving of meters can be quite simple or complex depending on the gas flow rate, temperature, pressure, and mixture. Low

pressure, low flow rate meters may be calibrated using water

displacement which is economical and can be quite accurate and precise.

Instruments for measurement of flow at several thousand cubic meters per

minute at pressures of .27 to 1.37 MPa can not be directly calibrated in

a routine manner, and therefore, infered methods must be used. These

methods currently involve construction of the meter to empirically

26
established specifications, water calibration to confirm basic meter

factors, and then modification of the meter factor to account for

compressibility and other non-ideal properties of the fluid to be

measured. Other methods of proving of high flow rate capacity meters

such as series operation with nozzles or multiple parallel meters are expensive and rely heavily on calculated performance rather than direct

experimental evidence.

A Steering Committee was formed to aid in the planning and review of

the Basic Natural Gas Metering Program. The committee is composed of

eight natural gas industry members and the NBS staff. The committee

met at NBS Boulder in October to review progress and has been instrumental in planning tests to establish the value of this new research

tool. Future meetings are planned on a two to three a year basis.

7. Program and Results . The demonstration of feasibility of the reference

system was completed in July, 1979. At that time, a standard four inch

orifice meter run was installed at the inlet to the gas test section and

subsequent testing involved a comparison of the performance of the meter

run to the reference system. This was only one of several procedures

used to establish the credibility of measurement. Performance of the

four inch orifice meter run followed the procedures of AGA Measurements

Committee Report No. 3. The intercomparison of the orifice run and the reference system for

several orifice sizes showed a reproducible and distinct flow dependence

relative to the NBS reference system. In an effort to define the cause

of this problem, a four inch gas turbine type flow meter was placed

downstream in series with the orifice run. The gas turbine had been

previously calibrated on a gas industry facility using natural gas as the process fluid and choked nozzles as the flow reference. Testing of

this combination only confirmed the flow dependence results by showing a good agreement between the gas turbine meter and the NBS reference

system.

In addition to the orifice meter flow dependence, large flow dependent

pressure fluctuations were observed in the measurement of orifice

differential pressure. A number of tests were conducted to locate the source of these fluctuations and to relate, if possible, the magnitude

of the fluctuations to the flow measurement dependence. All tests were unproductive

.

A separate four inch orifice run was tested on the gas industry test

facility and confirmed the performance of this meter type to that

predicted by the AGA Measurements Committee Report No. 3. Therefore,

the problem then centered on the NBS reference system and the location

of the orifice run in this system.

The relative position of the orifice meter and gas turbine meter were reversed and it was shown that both the flow dependence and the pressure

fluctuations were markedly reduced if not eliminated. The reasons for

this improvement are still under investigation and the current work

continues to stress measurement credibility of the NBS reference system

and performance of the orifice meter in pipe sizes 2, 3, 4 and 6 inches

.

8. Problem Areas . The above investigations have delayed the progress of

the program and the establishment of a statement of total reference

system flow measurement uncertainty. At the present time no technical

barriers are foreseen in the accomplishment of the program objectives.

27
9. Level of Effort . January 1 - June 30, 1980

Staff-years expended

Equipment and/or Services Purchased

Approximate expenditures, total

1.5

$ 26,000

$ 121,000

10. Future Plans . A test plan will be developed to provide data on orifice

run pipe sizes 2, 3, 4, and 6 inch diameter with seven different orifice

plate diameters per line size. It is anticipated that data on the four

inch line size can be completed. A major effort will be made to develop

and publish a statement of total uncertainty of the gas flow reference

system

28
I Preprint I

| AGA Transmission Conference I

| Salt Lake City, Utah May 5-7, 1980 I

| Session 17 f

GAS MASS FLOW REFERENCE SYSTEM

A PROGRESS REPORT

Douglas Mann, James A. Brennan and C. H. Kneebone

Thermophysical Properties Division

National Engineering Laboratory

National Bureau of Standards

Boulder, Colorado 80302

AESTRACT

A new type of gas flow reference system under development at the National Bureau

of Standards is described. The closed loop system allows continuous flow of

nitrogen gas at line pressures of 4.1 MPa (600 psi a ) and at ambient

temperatures. The gas flow is then cooled to liquid nitrogen temperature, and

weighed at low pressures and at a density of up to 17 times the density in the

gas phase. This results in direct, accurate and precise mass flow rate

measurements.

This new flow reference tool is currently undergoing extensive testing and

evaluation to establish total system uncertainty relative to national standards

of mass. The program sponsored by the Gas Research Institute and the American

Gas Association, Inc., will be directed to improving accuracy and precision of

natural gas flow measurements, such as new gas flow data on orifice meter

discharge and expansion coefficients.

A description of the NBS process is provided as well as preliminary performance

information. Present mass flow rates are from 3000 kg/h (6600 lb/h) to 10000

kg/h (22000 lb/h) and plans for increasing this range are presented.

Key Words: Gas, Mass Flow, Fluid Flow, Instrumentation, Measurement, Metering,

Thermodynami cs

This work was conducted at the National Bureau of Standards under sponsorship of

the American Gas Association, Inc. and the Gas Research Institute.

Official contribution of the National Bureau of Standards, not subject to

copyright in the United States.

29
INTRODUCTION

The new gas flow reference system developed as a logical extension of a cryogenic flow metering reference system in operation at the National Bureau of

Standards Laboratories located at Boulder, Colorado. This liquid nitrogen system was part of a joint government-industry program designed to develop a National Model Code for Cryogenic Flow Metering which was successfully completed

in 1976. Descriptions of the program appear in the literature [1 to 9].

The concept of extending the cryogenic flow reference system to gaseous flow

operation was proposed by Mann and Brennan [10] in 1977. Funding to modify the

existing facility to demonstrate feasibility was made available from NBS and the

gas flow operation was demonstrated in July of 1979. Industry funding was made

available in late 1979 for a program which would continue the cryogenic capability and at the same time provide a gas flow reference system of high accuracy

and precision to study a range of current gas metering problem areas. This NBSgas industry effort is directed through a joint steering committee which plans

program objectives, reviews current progress and aids NBS in the selection of

experiments directed at current gas metering problems.

30
PROCESS DESCRIPTION

The process is shown schematically in figure 1. Basically, the process is a closed loop thermodynamic cycle. The process fluid, nitrogen, is circulated

between temperature limits of 85 K (153 R) and 300 K (540 R) at pressures of 0.5

MPa (75 psia) to 4.1 MPa (600 psi a ) depending on the point of the cycle under

consideration. Work is done on the system by centrifugal pumps operating at 85 K (153 R) which increase the liquid nitrogen pressure to 4.1 MPa (600 psia) from

0.5 MPa (75 psia). Heat energy enters the system through a steam heat exchanger

which controls the gas temperature at the test section. Heat energy is

extracted from the system by refrigeration provided by boiling liquid nitrogen

in the subcooler, auxiliary liquid nitrogen introduced at the main heat

exchanger and cooling at the water heat exchanger following the gas test

section.

The low pressure cryogenic portion of a cycle is maintained at a pressure of 0.5

MPa (75 psia) by means of helium gas introduced at the catch and weigh tank.

This inert pressurant provides necessary over-pressure to inhibit boiling of the

liquid nitrogen, allows liquid phase-gas phase separation for weighing of the

liquid nitrogen and provides a controlled environment for the stable operation

of the load cell and calibration weights. The interaction of the helium with

the liquid nitrogen is negligible as the solubility of helium in liquid nitrogen

is less than 0.1 percent. Pumping of the process fluid is accomplished in two

steps. The boost pump increases the pressure about 0.2 MPa (25 psi) to the

suction of the pressure pump. The pressure pump in turn raises the process

fluid pressure to 4.1 MPa (600 psia). Both pumps are centrifugal types. The

boost pump speed is variable while the pressure pump speed is fixed at about

8400 revolutions per minute. Mass flow rates are varied by operation of the

expansion valve.

Selection of the high side pressure of 4.1 MPa (600 psia) was deliberate. The

critical pressure of nitrogen is 3.4 MPa (493 psia) and operation above this

pressure avoids two phase liquid-vapor boiling and condensing in the main heat

exchanger, a possible source of flow noise.

The main heat exchanger is a five pass, plate-fin type constructed of aluminum.

Cross section is 63.5 cm (25 inches) by 33 cm (13 inches) and is 4.92 meters

(194 inches) in overall length including manifolds. The thermal load on the

heat exchanger varies from 300,000 J/s to 1 million J/s (one million to 3.2 million Btu/h) depending on flow rate. Operation of the exchanger near the critical pressure requires additional heat transfer surface because of severe internal temperature pinch at the low temperature end. Figure 2 shows the internal

temperature differences between the two counter-flow process streams for a set

of typical operating conditions. As a result of this condition and the requirement for additional heat transfer surface, nearly 80 percent of the heat

exchanger length is at a temperature of less than 150 K (270 R). To protect the

exchanger from environmental heat leaks, polyurethane foam insulation was applied to a thickness of 30 cm (12 inches).

31
Figure 1

.

Flow

Schematic

of

Gas

Maas

Flow

Reference

System

32
UJ

ccZD

f—

«=c oz

LU

Qs

UJ

VO CM 00

>i ‘33N3y3dJIQ 3bni\/H3dW3i

33

Figure

2.

Cooling

Curve

of

Main

Heat

Exchanger
It is necessary to stabilize the process fluid inventory within the main heat

exchanger to assure steady state mass flow through the gas test section. A

control system suggested by Vander Arend [11] was made part of the main heat

exchanger design by the addition of three flow passes during fabrication. The

first of these additional passes is dead-ended at the cold end of the main

exchanger allowing a quantity of nitrogen to be trapped for the full length of

the exchanger. During startup, nitrogen is allowed to fill this pass at pump

discharge pressure of up to 4.1 MPa (600 psia). When the operating pressure has

been achieved the pass is valved off and the pressure within the pass is monitored. In effect, the pass becomes a gas thermometer and is sensitive to bulk

temperature of the entire heat exchanger. The pressure within the pass reflects

the average density of the exchanger. The final two additional passes allow

control refrigeration or heating to stabilize the exchanger inventory. If the

pressure in the gas thermometer pass increases, this indicates a bulk heating of

the exchanger and a loss of inventory. Refrigeration in the form of supplemental liquid nitrogen is forced through one of the two additional passes. This

additional refrigeration tends to reduce the bulk temperature of the exchanger

to the original set point. Preliminary design provided for warm nitrogen gas to

be forced through the final pass if the bulk exchanger temperature fell below

the set point, but in practice, this condition did not occur and the two additional passes were piped in parallel to provide added refrigeration and control.

Process fluid, nitrogen gas, leaves the main heat exchanger at a pressure of 4.1

MPa (600 psia) and near 0°C. The temperature is raised to gas flow standards

15.6°C (60 F) by means of a shell and tube steam heat exchanger located just

downstream of the main exchanger. Steam is supplied at U.Ub MPa (10 psia) at a flow rate of up to 114 kg/h (252 lb/h). The process fluid then enters the gas

test section for experimental measurements and returns to the main exchanger. A shell and tube water heat exchanger removes a portion of the heat energy added

at the steam exchanger and provides additional temperature stabilization of the

process. Process fluid is cooled in the main heat exchanger to below 100 K and

then is expanded in pressure from 4.1 MPa (600 psia) to 0.5 MPa (75 psia) at the

expansion valve. Refrigeration is supplied at the subcooler reducing the fluid

temperature to about 85 K. The process fluid can then be metered in the

cryogenic fluid test section or piped directly to the catch and weigh system.

The operation, accuracy and precision of the cryogenic catch and weigh system is

explained in detail by Dean, Brennan, Mann and Kneebone [5]. In summary, the

dump valve at the outlet of the weigh tank is held in the open position until

thermodynamic and porcess equilibrium has been established at a chosen flow

rate. This procedure allows liquid nitrogen under helium gas pressure to circulate through the catch tank to the pump suction. When a test draft is to be

run, the weigh tank valve is closed and sealed and liquid nitrogen accumulates e in the weight tank. The force resulting from the liquid accumulating in the

weigh tank is measured by the load cell which in turn has been calibrated in

reference to standard weights.

34
SYSTEM OPERATION

The system was run for the first time during July, 1979. During August, some preliminary data were obtained on a four inch orifice flowmeter that was obtained from the joint AGA-API Orifice Flowmeter project. This flowmeter was supplied with a set of six plates which gave a beta ratio range of 0.2 to 0.75.

For the preliminary tests a flowmeter with a beta ratio of 0.496 was installed.

This test was used to identify any serious problems associated with the system

and to get a first look at the comparison between the flow facility and flow

calculations based on AGA-3( 12 ) . Various system problems were identified that

caused fluctuations in the gas temperature at the orifice and a rather noisy

pressure signal at the orifice.

The problem with the gas temperature fluctuations was solved by changing the

flow control on a steam heat exchanger. This stabilized the heat exchanger

temperature and consequently the gas temperature.

Noise on the orifice pressure measurements has been more difficult to isolate

and eliminate. The measurements are made using pressure transducers which are then scanned and the data sent to a mini -computer for data reduction. Single

readings of the undamped signal are taken without any averaging, so the full

range of any flow noise is observed. The average of a square root of the indi

vidual readings are used for calculating the flow rate. Since this procedure is

not the normal recording method used by the gas industry, a parallel measurement

system was also installed. This parallel system used instruments commonly used / for natural gas orifice pressure measurements. This could be done because the

orifice flanges have double tappings.

The parallel instruments used were a differential pressure transmitter and a mercury recording manometer. A dry type flow recorder will also be tested later

in the program. In general the pressure transmitter, when operated in the

undamped mode, gave the same information as the original pressure transducer. By

increasing the damping with the built in electronic adjustment the pressure var- iations could be reduced by about 50%. The averages calculated using the damped

and undamped signal were the same, so the overall results did not change.

The recording mercury monometer was only used in the undamped mode. Even in

this mode the recorder was not able to duplicate the level of noise measured

with the pressure transducer or the transmitter. In general the recorded signal

exhibited a trace equivalent to about 498Pa (2 in. H2 O). Again the average

agreed with the calculated average from the pressure transducer.

Introduction of additional pressure drop at various locations in the system was investigated as a possible way of reducing the noise level. This effort was not

successful. Additional tests are planned to better define the noise source and

affect so that corrective measures can be taken if deemed necessary and feasible.

35
FUTURE PLANS

The immediate objective of the current program is to refine the data and procedures so that a total uncertainty of measurement may be documented. This

requires on the part of NBS a complete analysis of the system performance and

documentation of all calibration and measurement procedures. With this portion

of the program completed, the joint NBS-gas industry steering committee will

devise a plan to systematically investigate the orifice discharge and expansion

coefficients, flow conditioning and the general area of orifice plate

fabrication.

36
REFERENCES

1. ISA; Ad Hoc Committee Report of Flow Measurements, Instrument Society of

America, Pittsburgh, PA (1967).

2. D. B. Mann, Cryogenic Flowmetering at NBS, Cryogenics 11, 179 (1971).

3. J. W. Dean, J. A. Brennan and D. B. Mann, Cryogenic Flow Research Facility

of the National Bureau of Standards, Advances in Cryogenic Engineering, 14,

(Plenum Press, New York, 1969).

4. D. B. Mann, J. W. Dean, J. A. Brennan and C. H. Kneebone, Cryogenic Flow

Research Facility, (Unpublished NBS report to sponsor, January 1970).

5. J. W. Dean, J. A. Brennan, D. B. Mann and C. H. Kneebone, Cryogenic Flow

Research Facility Provisional Accuracy Statement, National Bureau of

Standards Technical Note 606 (1971).

6. J. W. Dean, J. A. Brennan, D. B. Mann and C. H. Kneebone, An Evaluation of

Cryogenic Positive Displacement Volumetric Flowmeters, National Bureau of

Standards Technical Note 605 (1971).

7. J. A. Brennan, R. W. Stokes, C. H. Kneebone and D. B. Mann, An Evaluation

of Several Cryogenic Turbine Flowmeters, National Bureau of Standards Technical Note 624 (1972).

8. J. A. Brennan, R. W. Stokes, C. H. Kneebone and D. B. Mann, An Evaluation

of Selected Angular Momentum, Vortex Shedding and Orifice Cryogenic Flowmeters, National Bureau of Standards Technical Note 650 (1974).

9. National Bureau of Standards, Specifications, Tolerances, and other Technical Requirements for Commercial Weighing and Measuring Devices, National

Bureau of Standards Handbook 44, 4th Ed. w/revisions (1976).

10. D. B. Mann and J. A. Brennan, On a New Method of Gas Flow Measurement Using

Cryogenic Techniques, National Bureau of Standards Special publication 484

(1977).

11. Mr. P. C. Vander Arend, private communication (1978).

12. American Gas Association, Inc., Orifice Metering of Natural Gas, Gas Measurements Committee Report Number 3, (1972).

37
1 . Title . LTOIIFFIFn NATURAL GAS TECHNOLOGY TRANSFER

Principal Investigators . D. E. Diller, H. M. Ledbetter, L. L. Sparks,

and N. A. Olien

2. Cost Center Numbers . 7730403, 7734574, 7738574, 7730594, 5621510

3. Sponsor Project Identification . Maritime Administration, Miscellaneous

Purchase Order No. 400-79005; American Gas Association, Inc. Project

BR-50-10; Gas Research Institute; NBS Office of Standard Reference

Data

4. Introduction . The liquefied natural gas program at the Thermophysical

Properties Division of NBS Boulder represents an investment by industry

and government agencies of over $7 million over the past six years.

This investment was designed to develop reference quality properties

data for both fluids and materials and instrumentation and measurement

technology for the use of the LNG and related industries. Information

developed under this program must be transmitted to the ultimate user in

a timely and useful format. The classical publication methods of NBS

most certainly provide the scientist and research engineer information

in a form most useful to the academic or near academic community.

However, as a result of extensive assessments of user requirements, it was found that an additional effective mode for technology transfer

would be an LNG Materials and Fluids User's Manual. A complete outline

and planned table of contents have appeared in previous semiannual

reports. The Maritime Administration of the Department of Commerce and

the American Bureau of Shipping agreeded to sponsor the first year's

efforts on the materials section, and the American Gas Association, Inc.

and the NBS Office of Standard Reference Data agreeded to sponsor the

section on fluids and fluid mixtures. The project was begun on April 1,

1976 .

5. Objectives or Goals . The Liquefied Natural Gas Materials and Fluids

User's Manual will provide a method of quick dissemination of property

data and related information for the effective generation, utilization

and transportation of LNG. The object is to improve technology transfer

from the current NBS Thermophysical Properties Division LNG physical

measurements program to the users, including federal agencies, the

states and industry. For the purpose of this data book, liquefied

natural gas is defined as a cryogenic mixture (at less than

approximately 150 K) of hydrocarbons, predominantly methane, with less

than a total of 20% of the minor components ethane, propane, iso and

normal butane, and nitrogen as an inert contaminant. LNG materials will

be those associated with the liquefaction, transport and storage of

liquefied natural gas.

6. Background . The User's Manual is only one of a number of information

dissemination methods used to provide workers in the liquefied natural

gas (LNG) industry with properties data of known quality in a format

consistent with the requirements of the intended user. In the case of

the LNG User's Manual the intended audience is the field engineer, plant

manager, ship designer or process engineer interested in a ready

reference of assessed quality for data to be used in conceptual design,

process monitoring, process analysis, and intercomparisons where

precision and accuracy are secondary to specific problem solutions. The

hierarchy of accuracy and precision will be defined and traceable

through references to scientific and engineering literature.

Data are classified into three groups by the NBS Thermophysical

Properties Division.

38
Group 1 . Data which have been generated experimentally by NBS , or have

been assessed, evaluated or experimentally verified by NBS.

Group 2 . Data which have been assessed and evaluated by NBS.

Group 3 . Data available in the scientific engineering literature

through the NBS Cryogenic Data Center or elsewhere. No NBS evaluation

or assessment has been made at this date.

In general, most data included in the LNG User's Manual is from groups 1 and 2. Few new assessments or correlations are anticipated or required

for this work.

Data are presented primarily in graphical form. Tables and analytical

expressions are used only where absolutely necessary. Graphs and charts

are in loose-leaf form for ease of updating and additions. This form

also allows immediate implementation of data already available under the

NBS LNG program and provides a convenient format for the output of data

from existing projects. The User's Manual is not be a substitute for

traditional publications in the scientific literature where measurement

science, technique, precision and accuracy are paramount, but provides

the data and references for the necessary assessment by the user. The publication of both graphical and tabular data is in a dual system

of physical units. These units are the traditional LNG industry British

System of BTU , pound, degree Fahrenheit and the SI system of joule,

kilogram and kelvin. It is the intent to give equal weight to each

system of units.

7. Program and Results . The first edition of the User's Manual became

available for distribution in September 1977. A complete description

and ordering information are included as part of this report. Over 850

copies have now been distributed to sponsors and purchasers. New orders

are currently coming in at the rate of about ten per week. The first

supplement to the User's Manual is printed and 500 copies have been

d istr ibuted

On January 24, 1979 the LNG Materials and Fluids User's Manual received

the Award of Distinction (first place) of the Society for Technical

Communications. This award was in the category "Industrial Handbooks

and Manuals" and we believe recognized the efforts and contributions of

the sponsors and individual contributors.

Due to an initial uncertainty about the demand for the User's Manual

only 750 of the cover and dividers were ordered, however 1000 copies of

all graphs and text were printed. Our original stock of 750 was exhausted in April, therefore 250 additional covers and divider sets were ordered and are now in use for filling orders.

The second supplement has been completed. The second supplement

contains 28 graphs on composites, 6 on concrete, 27 updated graphs on structural materials, 15 graphs and 3 wall charts on propane properties

and three graphs on mixture properties. 686 copies of the second

supplement have been distributed since it became available for

distribution in January.

8. Problem Areas. None.

39
9. Level of Effort . January 1 - June 30, 1980

0.1

14 . 3K$

7 . 5K$

Staff-years expended

Equipment and/or Services Purchased

Approximate expenditures, total

10. Future Plans . This work is now essentially complete, except to continue

distribution of the second supplement as well as the few remaining

copies of the previous versions of the User's Manual.

40
- - - - -- —

U.S. DEPT. OF COMM.

BIBLIOGRAPHIC DATA

SHEET

1. PUBLICATION OR REPORT NO. NBSIR 80-1636

3. Recipient' $ Accession No,

4. TITLE AND SUBTITLE

Liquefied Natural Gas Research at the National Bureau of

Standards

5. Publication Date August 1980

7. AUTHOR(S)

Douglas B. Mann

8. Performing Organ. Report No.

9. PERFORMING ORGANIZATION NAME AND ADDRESS

NATIONAL BUREAU OF STANDARDS

DEPARTMENT OF COMMERCE

WASHINGTON. DC 20234

ml

' ' '

11. Contract/Grant No.

12. SPONSORING ORGANIZATION NAME AND COMPLETE ADDRESS (Street, city, state, ZIP)

See page ii

13. Type of Report & Period Covered

15. SUPPLEMENTARY NOTES

| 1 Document describes a computer program; SF-185, FIPS Software Summary, is attached.

16. ABSTRACT (A 200-word or less factual summary of moat significant information. If document includes a significant bibliography or

I literature survey, mention it here.)

i The objective of this report is to:

j 1. provide all sponsoring agencies with a semiannual report on the activities

of their individual programs;

1

II 2. inform all sponsoring agencies on related research being conducted at the

NBS-NEL Themc^hysical Properties Division, NBS-NEL Mechanical Processes

Division and NBS-NML Fracture and Deformation Division;

3. provide a uniform reporting procedure which should maintain and improve

communication while minimizing the time, effort and paperwork at the cost

center level.

The work is supported by NBS and seven other agencies and represents the

collective expenditure of $646,000 during the 6 month reporting period. The contents

of this report augment quarterly progress meetings for certain of our sponsors and

provide a perspective which is missing when the parts are viewed individually.

' Distribution of this document is limited and intended primarily for the supporting

agencies. Data or other information must be considered preliminary, subject to

change and unpublished, and therefore not for citation in the open literature.

17. KEY WORDS (six to twelve entries ; alphabetical order; capitalize only the first letter of the first key word unless a proper name;

separated by semicolons)

Cryogenics; liquefied natural gas; measurement; methane; properties; research.

18. AVAILABILITY Unlimited 19. SECURITY CLASS

(THIS REPORT)

21. NO. OF

PRINTED PAGES

XXI For Official Distribution. Do Not Release to NTIS UNCLASSIFIED

| | Order From Sup. of Doc., U.S. Government Printing Office, Washington, DC

20402, SD Stock No. SN003-003-

20. SECURITY CLASS

(THIS PAGE)

22. Price

| | Order From National Technical Information Service (NTIS), Springfield, V A. 22161 UNCLASSIFIED

U S COMM- DC