摘要:

AbstractA theoretical analysis of the behavior of gas bubbles in vertically vibrating liquid columns is presented. The theoretical approach predicts the depth in liquids at which the downwards force, due to vibrations, acting on single bubbles just balances the buoyancy force, i.e. the depth of no net movement of given bubbles. Theoretical results predicting the direction of movement of bubbles were obtained for various diameters over a wide range of frequencies, amplitudes, liquid viscosities and densities. Agreement with published experimental work is good.

ISSN:0008-4034    

DOI:10.1002/cjce.5450460301

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1968

数据来源: WILEY

摘要:

AbstractA study on the flow of power‐law fluids through a multi‐particle system including both fixed bed and fluidized bed is presented. Equations for the pressure drop, the minimum fluidization velocity, and the bed expansion are obtained by extending the Blake‐Kozeny's equation for the pressure drop through packed beds to power‐law fluids. Bed expansion equations are also obtained by extending the Richard‐son‐Zaki's theory for the drag force in a multiparticle suspension to power‐law fluids. These equations are compared with expe

ISSN:0008-4034    

DOI:10.1002/cjce.5450460302

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1968

数据来源: WILEY

摘要:

AbstractA method to obtain bounds on the integral and instantaneous rate of diffusion and mass transfer controlled gas solid reactions in spherical particles is developed. It is shown that the pseudo steady approximation is valid during most stages of reaction even under time dependent ambient conditions.

ISSN:0008-4034    

DOI:10.1002/cjce.5450460303

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1968

数据来源: WILEY

摘要:

AbstractPrevious studies of the pipeline movement of single paste slugs of coal have been extended to determine the velocities of, and the pressure gradients along, trains of slugs. The measurements were taken in a 70‐foot long, closed‐loop line made from 0.95‐inch bore, rigid plastic tubing. Flow in the line could be switched to maintain continuous movement of a train of slugs.Tests were made with slugs of 80:20 (w/w) coal‐water paste which was extruded through a 0.775‐inch die and also with slugs which were stabilized by the addition of agar to the water used for making the slugs. Slugs made from coal and agar solution were formed in cylindrical molds having diameters of 0.567, 0.661 and 0.756 inches and were intended to show more clearly the influence of slug diameter on the behavior of the trains. Individual slugs were five inches in length and were formed into trains with lengths of up to fifteen feet for the tests. The oil used as carrier fluid was a light mineral oil (μ = 5.92 cp,σ = 0.826 at 70°F.), which was circulated through the pipeline loop at velocities ranging from 1.0 to

ISSN:0008-4034    

DOI:10.1002/cjce.5450460304

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1968

数据来源: WILEY

摘要:

AbstractThe packing density of a multi‐particle system is found to increase if the particle size distribution is extended. Results are reported for Gaussian and log‐normal size distributions using dense random packing of two sands with particle sizes of front<0.07 to 8.0 mm.Packing density is shown to be a function only of size distribution represented by a dimensionless standard deviation, and of particle shape. It is independent of particle size.Packing densities of binary mixtures of continuously distributed systems are found to depend upon the composition of the mixture, the mean‐size ratio of the components of the binary, and upon the packing density of the individual components. Maxima occur at compositions of 55 to 75% larger component, and increasing mean‐size ratios result in greater packing densities.The “increase in packing density” factor is a useful function for comparing, and setting limits to, packing densities of binary mixtures.The results should allow improved prediction and control of packing densities of many commonly encountered parti

ISSN:0008-4034    

DOI:10.1002/cjce.5450460305

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1968

数据来源: WILEY

摘要:

AbstractA modified principle of congruence is applied to the prediction of heats of mixing of binary systems. The principle is here applied to n‐alkanes binary mixtures and its application to other binary mixtures is also examine

ISSN:0008-4034    

DOI:10.1002/cjce.5450460306

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1968

数据来源: WILEY

摘要:

AbstractThis paper is concerned with the mathematical representation of an existing box‐type furnace for the thermal dehydrogenation of ethane. The furnace is composed of a preheating convection section and a radiant heated section. The two models considering (i) the tube‐side calculation and (ii) the radiant heat transfer in the combustion chamber are independent of each other.A study is made of the effects of pressure, heat flux level and “steam/hydrocarbon” ratio on the effluent composition. A significant improvement in reactor operation if a more uniform heat flux could be achieved is predicted.From the radiant heat transfer computations an unexpected variation in flame temperature in the furnace under study was d

ISSN:0008-4034    

DOI:10.1002/cjce.5450460307

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1968

数据来源: WILEY

摘要:

AbstractThe kinetics of the reaction of oxygen with sodium sulphite in aqueous solution without and with a catalyst of cobaltous sulphate have been studied by a flow thermal method.The rate of reaction of oxygen and sodium sulphite was found to be first‐order with respect to oxygen and variable order with respect to sulphite, and the promoting effect of cobaltous catalyst was proportional to its concentration. A reaction mechanism has been proposed and a rate expression derived which is in good agreement with the experimental dat

ISSN:0008-4034    

DOI:10.1002/cjce.5450460308

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1968

数据来源: WILEY

摘要:

AbstractThe distribution of fiber or polymer lengths during breakage is considered. It is shown that under certain conditions the distribution of lengths is given by a self‐preserving form which is independent of the initial distribution and is not explicitly dependent on time. Some self‐preserving distributions are calculated. The theory is compared with an experiment on the breakage of glass fibres caused by mill

ISSN:0008-4034    

DOI:10.1002/cjce.5450460309

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1968

数据来源: WILEY

摘要:

AbstractThree electrical effects in an approximately stoichiometric propane‐oxygen flame seeded with aluminum powder were studied: a) increase in flame current caused by the addition of aluminum, b) effect of transverse electrical field on the rate of aluminum oxide deposition onto a solid surface, c) effect of the field on the rate of heat transfer to a flat plate immersed in the flame. The maximum field was limited by breakdown to about 450 v/cm. It appears that the oxide deposition rate and the heat transfer rate can be influenced by relatively small electric field

ISSN:0008-4034    

DOI:10.1002/cjce.5450460310

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1968

数据来源: WILEY