bluuebunny/crossref_metadata_2025_split huggingface dataset:
Agitation of viscous Newtonian and non‐Newtonian fluids
Authors: Metzner A. B. , Feehs R. H. , Ramos Hector Lopez , Otto R. E. , Tuthill J. D. 
Published: June 2004

AbstractViscous fluids are frequently agitated by multiple impellers and in vessels only slightly larger than the impeller. This paper presents data for both Newtonian and non‐Newtonian fluids agitated under such conditions. The large decreases in power requirements (at a given level of mixing rate in the non‐Newtonian system) which are possible by use of low tank diameter, impeller diameter ratios and/or two impellers, have been quantitatively studied.The types of impellers used in the non‐Newtonian work and the ranges of conditions over which power requirement correlations were developed are summarized as follows:

D
T/D
n
NRe

Marine propeller
0.42‐1.0
1.4 ‐4.8
0.16‐1.0
0.67‐1320

Fan turbine
0.33‐0.67
1.3 ‐3.0
0.21‐1.4
6.6 ‐160

Flat‐Bladed turbine: one impeller
0.17‐0.67
1.3 ‐5.5
0.20‐1.5
2.0 ‐1800

two impellers per shaft
0.33‐1.00
1.023‐3.5
0.14‐1.00
0.15‐620

The results generally confirm an approach developed earlier, for the broader ranges of variables listed above. For the non‐Newtonian fluids of primary interest in this study, that is purely viscous materials having flow behavior indexes of less than unity (pseudoplastics, Bingham plastics), the prediction of power requirements has been developed to nearly the same level of perfection as for Newtonian fluids.
Heat transfer characteristics of porous rocks: II. Thermal conductivities of unconsolidated particles with flowing fluids
Authors: Kunii Daizo , Smith J. M. 
Published: June 2004

AbstractExperimental heat transfer studies were carried out in beds of unconsolidated glass beads and sand through which fluids were flowing. The scope of the measurements included four fluids, helium, air, carbon dioxide, and water liquid at atmospheric pressure in beds packed with four sizes of glass beads, 110, 370, 570, and 1,020 μ and with two sizes of sand, 110 and 240 μ. Flow rates ranged form 1 to 26 lb./(hr. sq.ft.) in a direction parallel and countercurrent to energy flow.The data were interpreted in terms of apparent, effective thermal conductivities of the bed. The values of ke increase significantly with mass velocity of fluid.By considering the mechanism of heat transfer in porous media a relationship was developed between ke and the heat transfer coefficient between fluid and particle. Treatment of the experimental data in this fashion, combined with available information for larger particles, results in a correlation of Nusselt and Reynolds numbers for air that covers the range N = 10−1 to 104.
A quantitative treatment of the forgotten effect in liquid thermal diffusion
Authors: Baldeschwieler John D. 
Published: June 2004

AbstractThe influence of the concentration gradient on the density gradient in a thermal‐diffusion column is called the forgotten effect. A modification of the theory developed by Furry, Jones, and Onsager is proposed to include the effect of the horizontal concentration gradient. A sample calculation with the system toluene‐cyclohexane shows that the equations predict the proper behavior for a forgotten‐effect system.
Fluid ‐ particle mass transfer in a packed bed
Authors: Bradshaw R. D. , Bennett C. O. 
Published: June 2004

AbstractMass transfer coefficients have been measured for air flowing through a bed of naphthalene pellets. Results were obtained for ⅜‐in. spheres and for ½, ⅜, and ¼‐in. cylinders in a bed 4 in. in diameter and packed to heights varying from 5 to 10 in. Radial concentration profiles were obtained for some conditions, from which the radial variation of the mass transfer coefficient was determined. The point‐values of kg follow an equation of the form kg = a Gb. From mixed outlet concentrations, values of kgav and jd, corrected for the effect of axial diffusion, have been obtained for all the pellet sizes as functions of mass velocity and Reynolds number, respectively.
The effect of acoustic vibration on forced convective heat transfer
Authors: Lemlich Robert , Hwu Chung‐Kong 
Published: June 2004

AbstractIn an effort to study the effect of acoustic vibration on forced convective heat transfer, sound at resonant frequencies of 198, 256, and 322 c./sec., as well as sound at nonresonant frequencies, was imposed on air flowing at Reynolds numbers of 560 to 5,900 in the core of a horizontal, double pipe, steam to air, heat exchanger. Increases in Nusselt number of up to 51% in the nominally laminar region and up to 27% in the nominally turbulent region were obtained. The improvement peaked sharply at resonance and increased with both amplitude and resonant frequency. A qualitative dual mechanism is suggested, and correlations for the experimental results are presented.
The P.V.T.‐behavior of diatomic substances in their gaseous and liquid states
Authors: Byrne Robert , Thodos George 
Published: June 2004

AbstractThe critical compressibility factor has been used as a criterion for the correlation of the P.V.T.‐behavior in the gaseous and liquid states for the diatomic gases, nitrogen, oxygen, carbon monoxide, nitric oxide, chlorine, and hydrogen chloride. Reduced densities for these substances have been calculated from available literature data. These are presented as functions of reduced temperature and reduced pressure to produce extensive density correlations for nitrogen, oxygen, and carbon monoxide. These correlations exhibit similar behavior as expected from their similar critical compressibility factors.The validity of the critical compressibility factor as a correlating parameter has been verified by the favorable comparison of the P.V.T.‐behavior of substances other than diatomic gases including argon, krypton, xenon, and methane. These results indicate that the P.V.T.‐behavior of substances having critical compressibility factors of approximately 0.291 can be predicted from the reduced state correlation developed in this study as long as polarity effects are absent.
The thermal conductivity of hydrocarbon gases at normal pressures
Authors: Misic Dragoslav , Thodos George 
Published: June 2004

AbstractDimensional analysis has been applied for the correlation of the thermal conductivity of a gas to its temperature, molecular weight, heat capacity, and critical constants. This approach indicates that the groupk*λ/Cpshould be a function ofzcandTR, where λ =M1/2Tc1/6/Pc2/3. Experimental thermal conductivities of hydrocarbons at normal pressures (approximately 0.2 to 5 atm.) have been used to develop two relationships. The first is applicable to all types of hydrocarbons for 0.6 <TR< 3.0 with the exception of methane and the cyclic hydrocarbons belowTR= 1.0, for which the other relationship is applicable. These two relationships have been used to calculate thermal conductivities for twenty‐eight gaseous hydrocarbons for which experimental data are available. Calculated values for normal paraffins, isoparaffins, olefins, diolefins, acetylenes, naphthenes, and aromatics produce an average deviation of 2.4% from experimental values for 154 points considered.
Dispersed‐phase holdup in a rotating disk extraction column
Authors: Kung E. Y. , Beckmann R. B. 
Published: June 2004

AbstractA study has been made of the effect of column geometry and flow condition upon the dispersed‐phase holdup in an rotating disk type of extraction column. Variables investigated were stator opening, disk diameter, compartment height, rotor speed, and flow rates of the dispersed and continuous phases. The toluene‐water system, with the toluene dispersed, was used throughout the study. The radio‐isotope technique was used to measure the dispersed‐phase holdup.Results of this study as well as those of earlier investigators have been used to expand upon the design equations proposed by Logsdail, Thornton, and Pratt for estimating flooding rates and dispersed‐phase holdup in rotating disk columns. Modifications to increase the accuracy of prediction of these equations have also been suggested, while possible limitations in their application have been indicated.
The utilization of fission fragment energy for the fixation of nitrogen
Authors: Steinberg Meyer , Green Leon , Powell J. R. 
Published: June 2004

AbstractThe principles involved in designing a process for the production of fixed nitrogen by the direct use of fission fragment recoil energy are reviewed. The problems concerned with the radiation chemistry, development of fuel element, reactor design, and chemical process design are pointed out. Possible solutions to these problems incorporated in a complete plant design are presented. An economic evaluation, comparing the chemonuclear process with other conventional processes, is made. The conclusion is reached that at the present state of knowledge there does not seem to be any clear‐cut advantage over conventional processes, even based on a nuclear economy. However moderate research efforts should continue for further evaluation of this process.
Compressibility of real binary gas mixtures
Authors: Busch Joseph S. , Canjar Lawrence N. 
Published: June 2004

AbstractThe P‐V‐T‐x properties of binary gas mixtures and their dependence on reduced temperature and pressure have been reviewed in detail.A modified form of Kay's original method for estimating P‐V‐T‐x properties of mixtures is suggested for purposes of engineering calculations.
Liquid‐vapor equilibria in the hydrogen‐nitrogen and deuterium‐nitrogen systems
Authors: Maimoni Arturo 
Published: June 2004

AbstractA recirculation type of apparatus with a novel liquid‐sampling system was used to obtain liquid‐vapor equilibrium data for the hydrogen‐nitrogen and deuterium‐nitrogen systems at 90° and 95°K. and pressures up to 1,000 lb./sq. in. abs. The data obtained show an average scatter in liquid compositions of the order of 0.01%, thus proving the feasibility of the new liquid‐sampling system. The vapor samples are shown by thermodynamic analysis to scatter less than 0.1%. Deuterium is slightly more soluble in liquid nitrogen than hydrogen; the relative volatility is 1.198 at 90°K. and about 1.177 at 95°K. The relative volatility is practically independent of pressure; thus at 90°K. the relative volatility decreases from 1.198 at 100 lb./sq. in. abs. to 1.196 at 1,000 lb./sq. in. abs., but this range of values is well within the experimental error.
Some observations on the mechanics of drops in liquid‐liquid systems
Authors: Elzinga E. R. , Banchero J. T. 
Published: June 2004

AbstractData on the rate of rise and distortion of drops in several liquid‐liquid systems have been collected. These are compared with correlations developed by other investigators, and in some cases discrepancies between observed and predicted values are noted which do not seem to be related to any easily measured physical property. However evidence is given showing that they are most likely due to the presence of surface‐active materials. Photographs and shadowgraphs showing the nature of the flow around and behind moving drops are also included. The point of boundary‐layer separation on the drop surface as indicated by these photographs has been related to the internal drop circulation. It is the shift in this point of separation which is the primary cause for the reduction in drag of liquid drops as compared with solid spheres. A previous theory for the breakup of rain drops explains the existing data for drop breakup in liquid‐liquid systems.
Turbulent flow ballistics facility for particle momentum transfer studies
Authors: Torobin L. B. , Gauvin W. H. 
Published: June 2004

AbstractThis paper describes the calibration and use of an experimental installation which was specifically designed for the quantitative measurement of the drag coefficient of single particles moving with a turbulent fluid. The installation consisted of an 8‐in. I.D. wind tunnel with an 18‐ft. test section, preceded by an inlet grid arrangement designed to provide a flow with a symmetrical mean velocity profile and a flat central core having a nonperiodic spectrum of turbulence. The particles were launched at controlled entrance velocities into the core in a nonrotating manner by means of a particle accelerator, and axial motion was obtained. A hot‐wire anemometer was used to measure the flow turbulence parameters at two Reynolds numbers by means of probes inserted at various distances above the inlet grid section. These measurements included the radial and axial intensities, the axial turbulent energy spectrum, and the macro and microscales. An accurate record of the particle velocity history was provided by a new radiotracer velocity measurement technique. This information was then processed by an IBM‐650 program which supplied the drag coefficient as well as the instantaneous particle velocity, acceleration, rate of change of acceleration, Reynolds number, and relative turbulence intensity from the time‐distance data. The experimental facility was found to be well suited for general studies of momentum transfer phenomena in particulate systems at high relative intensities.
On the steady flow of a non‐Newtonian fluid in cylinder ducts
Authors: Schechter Robert S. 
Published: June 2004

AbstractThe flow of a power law fluid in cylindrical ducts is considered, with a variational principle evolved from minimum entropy considerations used. This principle is applied to flow in rectangular ducts and between two flat plates with the method of Ritz and Galerkin to determine the velocity profiles used. These velocity profiles are used to determine the relationship between the friction factor and the Reynolds number.
Effects of superheated vapor and noncondensable gases on laminar film condensation
Authors: Sparrow E. M. , Eckert E. R. G. 
Published: June 2004

AbstractA boundary‐layer analysis of laminar film condensation on a vertical plate has been carried out to study the effects of superheated vapor and noncondensable gases. For a pure, superheated vapor the effects of superheating on the surface heat transfer are accounted for by a simple modification of previously available results for saturated vapors. For a given temperature difference between the plate surface and the liquid‐vapor interface, superheating increases the heat transfer to the surface, but only to a modest extent for most practical situations. Although free convection was not included in the analysis, its role has been estimated to be small. For noncondensable gases the analysis shows that the presence of a few per cent of noncondensable in the bulk of the vapor causes a great reduction in the surface heat transfer. The fact that the predicted reduction is substantially larger than that found experimentally indicates that free convection, which is not included in the analysis, plays an important role when noncondensables are present.
Initiation of roll waves
Authors: Hanratty Thomas J. , Hershman Arnold 
Published: June 2004

AbstractThe theory proposed by Jeffreys to explain roll‐wave transition on a liquid surface is applied to the concurrent flow of a gas and liquid. Data are presented for the concurrent flow of air with water‐glycerine solutions, water‐butanol solutions, and water‐sodium lauryl sulfate solutions. Agreement is obtained between theory and experiment.
Kinetics of carbon deposition in a fluidized bed
Authors: Oxley Joseph H. , Secrest Arthur C. , Veigel Neil D. , Blocher John M. 
Published: June 2004

AbstractRate data have been obtained for the deposition of carbon films from methane and acetylene in fluidized beds of alumina, uranium dioxide, uranium monocarbide, uranium dicarbide, and a solid solution of uranium‐thorium dicarbide powders. These carbon films have been shown to provide excellent protection for the powdered fertile material against attack by hot concentrated nitric‐acid solutions. The coated uranium‐thorium dicarbide particles were also shown to be stable in humid air.
Transient studies of product distribution from a packed bed reactor
Authors: Kapner R. S. , Hoelscher H. E. 
Published: June 2004

AbstractThe distribution of reactants and products from a simulated fixed‐bed catalytic reactor has been studied. The concentration of both reactant and product in the effluent stream as a function of time has been measured following a sudden change in inlet concentration. The effect of various types and sources of holdup in the bed is discussed. This study is preliminary to further experimental investigations of the mechanism and the rate of exchange of product between a catalyst surface in a fixed‐bed reactor and the free stream.
Immersion sampling of spray droplets
Authors: Tate R. W. 
Published: June 2004

AbstractNearly all process involving sprays or aerosols are strongly affected by droplet size. The measurement of droplet size has therefore been attempted by numerous methods, including direct high‐speed photography, light absorptionor scattering, droplet cooling or freezing, and collection of droplets on coated slides or immersion cells. Although no method is entirely satisfactory, the immersion sampling technique has been successfully used both in research and industrial testing of atomizing devices. This method entails collection of dyed‐water droplets in sampling cells containing solvent or a similar immersion fluid. Photomicrographs of the droplets are then obtained for manual or automatic counting.Although immersion sampling has several recognized advantages, it is limited by the tendency of large, high‐velocity droplets to shatter and by the failure of very small droplets to impact on the cell. Another problem is interference by the shutter used to expose the spray. To help overcome these limitations the mechanics of sampling hollow or solid‐cone sprays was analyzed, and procedures were developed for selecting optimum cell and shutter configurations, sampling distance, and exposure time. Extension of the method to sprays comprised of two liquid streams and to sampling of oil droplets is also discussed.
High temperature pile irradiation of the n‐heptane‐hydrogen system
Authors: Miley George H. , Martin Joseph J. 
Published: June 2004

AbstractA pilot unit for the high‐temperature irradiation of flowing reactants was designed for the beam port of a nuclear reactor. Radiation‐thermal cracking of the n‐heptane‐hydrogen system was studied with molal H2/C7 ratios from 0 to 5 at 250 lb./sq. in., 600° to 750°F., 2 to 8 min. residence time, and up to 3,600 rep./min. Although conversions were low, the decomposition rate was significantly increased by radiation giving G values > 103. Product distributions were not significantly altered by radiation. These results, while different from low‐temperature data, appear consistent with other published high‐temperature results. Radiation yields were found to be reasonably linear with total dose from 0 to 14 krep., but a twofold increase was observed in passing from a molal H2/C7 ratio of 0 to 0.5.
The effect of rate of sampling on the transient behavior of thermogravitational thermal diffusion columns without reservoirs
Authors: Vichare G. G. , Powers J. E. 
Published: June 2004

AbstractIn experimental investigations of the transient behavior of batch thermogravitational thermal diffusion columns it is expedient to obtain more than one sample from the column during a single run. Such sampling modifies the true batch nature of the column and thereby influences the experimental measurements to some degree. A combined theoretical and experimental investigation was carried out to determine the extent of the influence of sampling rate and thereby provide a means of predetermining a suitable sampling rate.The theoretical analysis was made by approximating the intermittent sampling as a continuous flow through the column. The transport equation of Furry, Jones, and Onsager was applied in the analysis, and an analytical solution was obtained for small separations of equicomposition binary solutions. The series solution is presented in the form of a graph. Experimental data were obtained in two thermogravitational columns with different plate spacings to test the theory. The effect of sampling rate was investigated, and theory and experiments were found to be in good agreement. It is concluded that the theory is entirely adequate to permit the prediction of sampling rates which will yield the maximum number of samples without disturbing the true batch behavior of the column.
Interfacial area in liquid‐liquid mixing
Authors: Rodriguez Ferdinand , Grotz L. C. , Engle D. L. 
Published: June 2004

AbstractIn predicting interfacial area in liquid‐liquid systems there are several published reports which give different results. Differences in methods of measurement of interfacial area and impeller design and location account for some of these discrepancies.For one pair of liquids, 40 parts by volume of ethylhexanol and 60 parts water, it was found that over wide ranges of impeller size to tank size ratio (0.27 to 0.67) that equal power per unit volume gave equal interfacial area per unit volume.
Kinetic data from nonisothermal experiments: Thermal decomposition of ethane, ethylene, and acetylene
Authors: Towell Gordon D. , Martin Joseph J. 
Published: June 2004

AbstractA rigorous method was developed to account for nonuniform temperature distributions in the analysis of kinetic data. The rate constants cannot be determined directly since they are functions of temperature, so equations were derived and solutions developed for the substantially temperature independent kinetic parameters, activation energy, and pre‐exponential factor. A digital computer was used to evaluate numerically various integrals involved in the solution of the equations. The method developed here will be useful in all laboratory kinetic studies where limitations of heat transfer do not permit an isothermal experiment and in the analysis of kinetic data obtained from commerical or pilot plant units where the temperature distribution is nearly always nonuniform.Kinetic studies were made of the thermal decompositions of ethane, ethylene, and acetylene, all of which are high temperature fast reactions. The experimental conditions covered highly nonuniform temperature distributions with peaks from 730° to 1,330°C., a total pressure of 1 atm., varying amounts of nitrogen dilution, and residence times in the millisecond range.
Prediction of pressure drop in two‐phase single‐component fluid flow
Authors: Hatch M. R. , Jacobs R. B. 
Published: June 2004

AbstractData on pressure drop in two‐phase, single‐component fluid flow, both with and without heat transfer, are presented in terms of the Lockhart and Martinelli correlation parameters. The fluids used were trichloromonofluoromethane and hydrogen.The results are compared with the correlation curve recommended by Martinelli and Nelson and give frictional pressure drops that are about 40% lower than the curve. The reasons for the deviations are discussed in terms of the effects of friction factors, the existence of metastable equilibrium, accuracy of data and instrumentation, and calculation procedures.It is concluded that the Martinelli and Nelson correlation and a simple momentum pressure drop computation can be superposed to predict roughly the total pressure drop in tubes containing steady state, two‐phase, single‐component fluid flow with appreciable vaporization.