ISSN:0001-1541    

DOI:10.1002/aic.690010101

出版商:American Institute of Chemical Engineers    

年代:1955

数据来源: WILEY

摘要:

AbstractWater was vaporized into air, helium, and Freon‐12 in turbulent gas flow over a wet‐bulb thermometer and through a 1‐ft.‐diam. tower packed with 1‐in. Rasching rings.The wet. and dry‐bulb measurements indicate that the gas‐film mass transfer coefficient varies with the Schmidt number to the —1/2 power for flow perpendicular to single cylinders.Heights of a transfer unit, H.T.U., were measured in the packed tower for flow of the gases countercurrent to water over a range of gas and liquid rate. H.T.U. varied as the 0.9 power of the Schmidt group. When compared at equal values ofρu2(ρ = gas density,u= velocity), H.T.U. varied as the 0.47 power of the Schmidt group. With reference to the psychrometric study, the latter method of comparison of H.T.U.'s seems preferable and indicates that further study of criteria for dimensional similitude in packed colu

ISSN:0001-1541    

DOI:10.1002/aic.690010102

出版商:American Institute of Chemical Engineers    

年代:1955

数据来源: WILEY

摘要:

AbstractA study was made of the mutual solubility of ethylene with various polar and nonpolar relatively high‐molecular‐weight organic compounds at temperatures 1° and 10° C. respectively above the critical temperature of ethylene and at pressures up to 1,500 Ib./sq.in.abs. For many compounds Henry's law was found to be applicable for the liquid phase up to approximately two thirds of the critical pressure of ethylene. In the critical region the solubility of ethylene was extremely sensitive to small changes in both temperature and pressure. The various types of phase behavior encountered were classified according to the nonideality involved. The results of this investigation indicate that a gas near its critical conditions is often capable of dissolving relatively nonvolatile materials in sufficient concentrations to warrant consideration of a separation process using such a gas as the extracting medium, namely fluid‐liquid ext

ISSN:0001-1541    

DOI:10.1002/aic.690010103

出版商:American Institute of Chemical Engineers    

年代:1955

数据来源: WILEY

摘要:

AbstractAlthough considerable work has been done on the problem of heat transfer radially in fixed beds through which gases are flowing, the data available for mass transfer are limited to one pipe size and one packing size and refer to average diffusivities for the entire bed. The present study was undertaken to determine: (1) diffusivities over a range of pipe and packing sizes and (2) the effect of radial position in the bed.The measurements were made by introducing carbon dioxide into an air stream and analyzing the resultant mixture at various positions in the bed downstream from the point of injection. Pipe sizes of 2, 3, and 4 in. were packed with spherical particles of 5/32‐, 1/4‐, 3/8‐, and 1/2‐in. nominal diameter.The differential equation describing the concentration in a packed bed when diffusivityEand the velocityuare permitted to vary with radial position was solved by use of an I.B.M. card‐programmed calculator for the computations.The results show that the Peclet numberDpu/Eincreases from the center towards the wall of the pipe and that the increase is significant whenDp/Dtis greater than 0.05. Empirical correlations are then presented for both point Peclet numbers, which vary with radial position, and average Peclet numbers for the entire bed.The variations in Peclet number with radius can be explained in terms of the corresponding variation in void fraction for 81% of the radius of the bed. At modified Reynolds numbers above 40 to 100 the equationPe= 8.0 + 100 (δ — δ0) correlates the effects of pipe and packing size and radial position. At radial positions greater than 0.81 wall friction influences turbulence conditions and the

ISSN:0001-1541    

DOI:10.1002/aic.690010104

出版商:American Institute of Chemical Engineers    

年代:1955

数据来源: WILEY

ISSN:0001-1541    

DOI:10.1002/aic.690010105

出版商:American Institute of Chemical Engineers    

年代:1955

数据来源: WILEY

摘要:

AbstractThe steady motion of single drops of ten organic liquids falling through a stationary water field is discussed. A correlation is presented for nine systems with the exception of the aniline‐water system, in the form of a single curve relating the drag coefficient, Weber number, Reynolds number, and a physical property group. The curve can be used directly to predict the terminal velocity, drag coefficient, Reynolds number, and Weber number for any given equivalent drop size.A break point in the curve serves to predict the peak velocity and its related quantities. The critical drop size is predicted from the pertinent physical properties alone. All these estimations were accurate within 10% for the systems used. The interfacial tensions ranged from 24 to 45 dynes/cm. and the drop densities from 1.100 to 2.947g./ml., the latter resulting in a twentyfold range of density differences. The drop viscosities had no apparent effec

ISSN:0001-1541    

DOI:10.1002/aic.690010106

出版商:American Institute of Chemical Engineers    

年代:1955

数据来源: WILEY

摘要:

AbstractData were obtained on the solubility of ethylene oxide gas in a number of aqueous and nonaqueous solvents at various temperatures and gas concentrations. Its absorption from high concentrations in air was studied in a packed column with a cooling jacket for removal of the heat evolved. The results can be correlated with adequate accuracy in terms of the conditions at the top or dilute end of the column. The values of (H.T.U.)Gand (H.T.U.)Lagree approximately with known values for other systems. For the solvents tested, the liquid‐film resistance is controlling at room temperature

ISSN:0001-1541    

DOI:10.1002/aic.690010107

出版商:American Institute of Chemical Engineers    

年代:1955

数据来源: WILEY

摘要:

AbstractA heated jet of air from an 0.898‐in. standard A.S.M.E. nozzle was discharged into a 4‐in. steel duct, well insulated over its entire 10‐ft. length. Air from the region surrounding the nozzle was entrained into the duct. At a number of points along the duct, radial profiles of air velocity and temperature were obtained by means of a probe which combined an impact tube and a thermocouple. The temperature at each of several points along the duct wall was indicated by thermocouples imbedded in the wall.In the experiments reported here the velocity at the jet was 585 ft./sec.; the temperature of the jet was about 220°F. and that of the entrained air was about 88°F. The total air flow rate through the duct was 0.67 lb./sec., and the heat flux was 4.9 B.t.u./sec., with the temperature of the entrained air taken as the datum.The radial and axial profiles of velocity and temperature are compared and discussed; the temperatures of the stream near the duct wall and of the duct wall itself are given. Conservation of mass and heat was checked by graphical integration of the radial p

ISSN:0001-1541    

DOI:10.1002/aic.690010108

出版商:American Institute of Chemical Engineers    

年代:1955

数据来源: WILEY

摘要:

AbstractThis paper concerns the kinetics of the processes that take place when a high‐velocity jet of fluid mixes turbulently with a low‐velocity, induced stream of the same fluid in a duct of uniform diameter. Semi‐two‐dimensional solutions of the equations of transport involving two empirical coefficients were obtained by application of Reichardt's hypothesis and three assumptions:(a)a negligible fraction of the flow entity (energy, mass, or momentum) is lost at the wall and the presence of the boundary layer may be ignored,(b)the static pressure is uniform over a section of the duct, and (c) the turbulence pattern is similar to that in free jets except that the duct wall limits the growth of the scale of the turbulence. A mixing index, which is a measure of the degree to which the jet stream remains unmixed with the induced stream at any point, was defined and related to the geometry of the system and the flow parameters by means of the theoretical equation, and a method of evaluating the empirical coefficients for a typical case of momentum transport was de

ISSN:0001-1541    

DOI:10.1002/aic.690010109

出版商:American Institute of Chemical Engineers    

年代:1955

数据来源: WILEY

摘要:

AbstractThe data in the first paper of this series on the distribution of momentum and energy in nonisothermal air streams mixing in a straight duct were correlated by the methods described in the second paper. Mixing indexes were evaluated and used to correlate profiles of total momentum and stagnation temperature at various sections of the duct.

ISSN:0001-1541    

DOI:10.1002/aic.690010110

出版商:American Institute of Chemical Engineers    

年代:1955

数据来源: WILEY