摘要:

AbstractThe momentum and energy integral method of von Karman and Pohlhausen is used to solve the entrance heat transfer problem for a non‐Newtonian fluid in a flat duct. The initial temperature and velocity profiles are assumed to be flat. The fluid is assumed to obey the Ostwald‐de Wael model and its physical properties are assumed to be constant. Dimensionless expressions for temperature and velocity profiles are obtained by numerical methods.The results of this investigation indicate that, similar to the case of Newtonian fluid, the parameters which influence entrance heat transfer arex/bratio, Reynolds number and Prandtl number, provided these groups are properly defi

ISSN:0008-4034    

DOI:10.1002/cjce.5450410402

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

年代:1963

数据来源: WILEY

摘要:

AbstractA method is proposed for determining the relative number of solute gas and liquid phase transfer units by vaporising the solute and the solvent into air, and so using the relevant mass transfer data for the solvent to minimise differences in operating conditions on the measured value for mass transfer of the solute.Experimental soluteNOGand solventNGvalues are determined from the amount of solute and solvent vaporised together into air from a low solute concentration in the liquid solvent. TheNGof the solvent is used to calculateNGfor the solute, and then, knowingNOG, to calculateNLfor the solute. This method allows for variations in foam structure in different systems and gives more accurateNGandNLsolute values than those calculated from water vaporisation and oxygen desorption experiments.NGandNLresults are presented for the solutes methyl alcohol and acetone in the solvents water and carbon tetrachloride from vaporisation experiments in a 4″ diameter sieve tray colum

ISSN:0008-4034    

DOI:10.1002/cjce.5450410403

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

年代:1963

数据来源: WILEY

摘要:

AbstractObservations have been made of the presence of coalescence within an operating spray liquid‐liquid extraction column, and of the ease or difficulty of coalescence at the column interface. On the basis of a mechanism proposed to explain coalescence and checked against the observations, qualitative predictions can be made as to ease of coalescence for ternary situations where a solute is transferred between two liquids, each saturated with the main component of the othe

ISSN:0008-4034    

DOI:10.1002/cjce.5450410404

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

年代:1963

数据来源: WILEY

摘要:

AbstractThe absorption of carbon dioxide by sodium hydroxide solutions has been studied on a single sieve plate. For sodium hydroxide concentrations from 0.001 to 0.14 lb. mole/ft.3and for carbon dioxide concentrations in the gas phase from 0.8 to 1.9%, the results were correlated by the equation‐\documentclass{article}\pagestyle{empty}\begin{document}$$ \frac{{k_L^{\,\,*} a}}{{k_L a}} = 1 + 1.34\left\{ {\frac{{\sqrt {k''D_A C_B } }}{{k_L }}} \right\}^{0.9} $$\end{document}The rate of absorption was found to be a maximum with solutions approximately 0.125 lb.mole/ft.3total sodium and at temperatures close to 125

ISSN:0008-4034    

DOI:10.1002/cjce.5450410405

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

年代:1963

数据来源: WILEY

摘要:

AbstractA continuous thickener inclined at 50° to the horizontal was compared with a conventional vertical thickener. When used to thicken a pulp of precipitated calcium carbonate in water the capacity of the inclined thickener was at least twice that of a similar vertical unit.A method for obtaining an approximate estimate of the capacity of the inclined thickener from batch settling data is suggested

ISSN:0008-4034    

DOI:10.1002/cjce.5450410406

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

年代:1963

数据来源: WILEY

摘要:

AbstractSolvents of low electrical conductivity which contain polar solutes produce static charges when caused to flow through tubes of various materials. The resulting electrification has been found to be essentially independent of the solvent provided it is of low conductivity in the pure state. The magnitude and the sign of the charge produced are highly dependent on the chemical nature of the polar solute and of the containing tube.Currents resulting from the formation and relaxation of electrical charge were measured at various sites along the tubes. Local charge production was found to be greatest near such irregularities as constrictions in the tube. Tube constrictions resulted in sign reversal of local charge production. Large voltages of opposite sign could be produced on a single tube. Sparks could be drawn between two sections of the same tube a short distance apart.The recent theories dealing with the phenomenon of electrification have been discussed in the light of these findings.

ISSN:0008-4034    

DOI:10.1002/cjce.5450410407

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

年代:1963

数据来源: WILEY

摘要:

AbstractKinetic studies have been made of the thermal decomposition of precipitated calcium carbonate, powdered calcite, and regular fragments of calcite crystals. The powdered materials were examined in the form of pellets, which were prepared by compacting the powder to about 70% of its theoretical density. The work was done at one atmosphere of pressure in a flow of air containing various amounts of carbon dioxide. It was observed that the decomposition of the pellets, which were prepared in a variety of shapes, was characterized by the same advancing interface mechanism as that observed for single specimens of crystal fragments. When the rates of decomposition were normalized for the change in of interfacial area accompanying decomposition, it was possible to correlate the observed rates of decomposition for a variety of pellet shapes, and to relate these rates, as a function of particle size and pellet roughness, to the rates of decomposition of large fragments of calcite crystals. The activation energy for the decomposition reaction was found to be 40.6 kcal./mole. At a constant temperature, the decrease in reaction rate with increasing carbon dioxide pressure was found to be proportional to the difference between the equilibrium dissociation pressure and the back pressure of carbon dioxide. A reaction mechanism based on diffusion through a constant thickness of active calcium oxide is suggested.

ISSN:0008-4034    

DOI:10.1002/cjce.5450410408

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

年代:1963

数据来源: WILEY

摘要:

AbstractBased upon data reported in the literature, pressure‐temperature critical loci are presented for the methane‐ethane‐n‐butane and ethane‐n‐butane n‐pentane systems. Loci are drawn having fixed values of a composition parameter including the two heavy components of the system. The curves closely resemble the bounding binary loci. Based upon accurate methods of calculating critical temperatures (0.5%) and critical pressures (1.5%), critical loci are presented for the ethane‐propane‐n‐butane‐n‐pentane system. Two families of curves are generated, each family corresponding to a fixed value of the composition parameter including the heaviest components. Each curve corresponds to a constant ratio of propane, n‐butane, and n‐pentane (and to fixed values of two composition parameters). Relations are noted between binary and multicomponent mixtures containing a constant mole fraction of light component, and the concept of a pseudo‐heavy component is discussed. For a fixed value of the heavy component composition parameter, triangular composition diagrams with curves of constant critical temperature and constant critical pressure are presented for the ethane‐propane‐n‐butane‐n‐pentane system. Linear critical temperature parameters connecting the bounding binary and ternary systems adequately describe the critical temperature behavior of the quartenary system. The critical pressure beha

ISSN:0008-4034    

DOI:10.1002/cjce.5450410409

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

年代:1963

数据来源: WILEY

摘要:

AbstractA new method is proposed for analytical representation of binary excess thermodynamic properties, ΔGE, which is applicable in principle to all known types of curves except those exhibiting a minimum on a ΔGE/x1x2vs.x1plot. It is particularly useful for representing data for polar‐non‐polar systems such as alcohol‐aromatic hydrocarbon mixtures.The proposed expression contains 5 constants and in a number of cases reduces to a simple 3‐constant equation. All constants can be evaluated by simple graphica

ISSN:0008-4034    

DOI:10.1002/cjce.5450410410

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

年代:1963

数据来源: WILEY

ISSN:0008-4034    

DOI:10.1002/cjce.5450410411

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

年代:1963

数据来源: WILEY