摘要:

AbstractHeat transmission to agitated non‐Newtonian liquids in a jacketed vessel has been studied. Heat transfer tests were conducted under unsteady‐state conditions with pseudo‐plastic solutions (behavior index range: 0.343 to 0.633).For a generalized Reynolds number ranging from 100 to 5000, two correlations were found:\documentclass{article}\pagestyle{empty}\begin{document}$$ \begin{array}{lr}{{\rm Heating}\;{\rm data:}\,N_{Nu} = 3.41\,N_{Re'^{\frac{2}{3}} } N_{Pr ^{\frac{1}{3}} } } & {} \\ {} & {({\rm mean}\,{\rm deviation}\,{\rm :}11.8\%)} \\ {{\rm Cooling}\,{\rm data:}\,N_{Nu} = 1.43\,N_{Re'^{\frac{2}{3}} } N_{\Pr ^{\frac{1}{3}} } } & {} \\ {} & {({\rm mean}\,{\rm deviation}\,{\rm :}14.0\%)} \end{array} $$\end{document}The use of a generalized Sieder and Tate number resulted in an equation combining both heating and cooling data with a somewhat higher mean deviation (19.3%):\documentclass{article}\pagestyle{empty}\begin{document}$$ N_{Nu} = 1.474\;N_{Re'^{\frac{2}{3}} } N_{Pr^{\frac{1}{3}} } (\mu d_w /\mu d)_\alpha - 0.24/n. $$\end{doc

ISSN:0008-4034    

DOI:10.1002/cjce.5450440101

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

年代:1966

数据来源: WILEY

摘要:

AbstractEach of the two friction factors in an annulus is defined in terms of the average kinetic energy of the fluid in the region between the radius of maximum velocity and the appropriate wall. These friction factors thus defined can be uniquely correlated against corresponding Reynolds numbers. The correlation is excellent for the outer portion of flow for all values of the radius ratior1/r2, but not as good for the inner region of flow whenr1/r2is small. Applying the Colburn analogy, inner and outer wall j‐factors are similarly correlated with the same degree of accurac

ISSN:0008-4034    

DOI:10.1002/cjce.5450440102

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

年代:1966

数据来源: WILEY

摘要:

AbstractA formula is developed (from which a computer program has been written) that allows the temperature to be calculated of a granule that undergoes alernating periods of being cooled and of being allowed to ‘soak’ without cooling. This is the process, repeated many times, that a particle suffers in a rotary cooler. The result should provide a design method that utilizes only basic physical quantit

ISSN:0008-4034    

DOI:10.1002/cjce.5450440103

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

年代:1966

数据来源: WILEY

摘要:

AbstractNitrogen‐fluidized beds of petroleum coke and graphite were heated by applying an a.c. voltage to electrodes submerged in the bed. Bed resistivities, calculated from the voltage and power input required to maintain a constant temperature, show a similar decrease in resistivity, for both materials, with increasing temperature up to 600°C., however, at about 600°C. the resistivity of graphite beds continues to decrease while that of coke beds goes through a minimum and then increases.This was attributed to arc formation at the contacts between coke particles when the applied voltage exceeds a critical value. Similar behavior was not observed for graphite as the operating voltage never exceeded the critical va

ISSN:0008-4034    

DOI:10.1002/cjce.5450440104

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

年代:1966

数据来源: WILEY

摘要:

AbstractRates of sublimation mass transfer from an adiabatic sharp‐edged flat plate have been measured. The plate was coated with ice, naphthalene, thymol, and camphor (Schmidt number range 0.60 to 2.9) and exposed to parallel supersonic (Mach 3.28) air flow. The coating thickness decrease during the run was measured and surface temperatures and flow variables were monitored. Turbulent data were obtained over a Reynolds number range from 2 × 105to 106. The results show that at Sc>1 the effect of compressibility on mass transfer is greater than on heat and momentum transfer while at Sc<1 the effect is reversed. This is in qualitative agreement with theory; quantitative agreement was obtained only with ice. Sublimation data of Sherwood and Trass are reviewed brief

ISSN:0008-4034    

DOI:10.1002/cjce.5450440105

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

年代:1966

数据来源: WILEY

摘要:

AbstractThe transient behavior of a packed bed of uniform spheres is considered, where heat (or mass) transfer inside the sphere is described by a linear parabolic second order partial differential equation — the standard diffusivity equation. One dimenisonal plug flow is assumed; hence, the fluid behavior is given by a set of first order partial differential equations, with bed axial position and time as the independent variables. The existence of chemical reaction in the fluid makes these equations non‐linear. The two systems of equations describing the solid and the gas are coupled by the equations for heat (or mass) transfer at the surface. Numerical methods for solving both the linear (no reaction) and non‐linear (with reaction) cases are presented. In the former, the implicit Crank‐Nicholson method is used; in the latter the two systems of equations are first decoupled and then solved sep

ISSN:0008-4034    

DOI:10.1002/cjce.5450440106

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

年代:1966

数据来源: WILEY

摘要:

AbstractThe mathematical problems of reactor design and performance depend primarily on the solution of a set of partial differential or difference equations. These equations are linear if the reactions are first‐order, if temperature variations are not significant, and if mass transfer by diffusion obeys Fick's law. When a reactor problem can be solved for a single irreversible first‐order reaction, it can also be solved for a system of coupled first‐order reactions of any number of chemical species and of arbitrary compl

ISSN:0008-4034    

DOI:10.1002/cjce.5450440107

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

年代:1966

数据来源: WILEY

摘要:

AbstractThe recent PVT measurements of p‐hydrogen reported by the National Bureau of Standards(1,2,3)have been utilized to establish the Enskog modulus,bpx, for pressures up to 350 atm and temperatures up to 100°K. These conditions define both the gaseous and liquid regions and also include the saturation envelope from the triple point to the critical point of this substance. This modulus is expressed graphically as a function of reduced pressure and reduced temperature. The best available PVT measurements coupled with a precise calculational procedure conducted on an IBM 709 computer have produced abpxcorrelation which readily permits the calculation of the pressure dependence of the transport properties of p‐hydrogen according to the Enskog theory for the dense gaseous and liquid reg

ISSN:0008-4034    

DOI:10.1002/cjce.5450440108

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

年代:1966

数据来源: WILEY

摘要:

AbstractA series of experiments were made on the thermal separation of various mixtures of coal in oil using a fluidized bed reactor. The majority of experiments were carried out on a mixture of 30% w/w Edmonton coal in 70% w/w Leduc crude oil in a temperature range of 700–900°F. The products of the reaction were a char, an oil and a gas. At temperatures above 700°F. the solid particles became dry and free‐flowing; no agglomeration or channelling in the bed was apparent. An increase in reactor temperature in the 700–900°F. range decreased the amount of residual oil on the char from about 2% to 0.1% at the same time the heating value of the char rose from 11,900 to 12,600 Btu/lb. Carbon residue of the product oil was substantially less than that of the original oil, the reduction being about 50% in the case of Leduc oil and 75% for Lloydmin

ISSN:0008-4034    

DOI:10.1002/cjce.5450440109

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

年代:1966

数据来源: WILEY

摘要:

AbstractThe parameters introduced by Lockhart and Martinelli to correlate pressure gradients accompanying the flow of gas‐liquid mixtures in horizontal pipes have been found to be useful in correlating data for the stratified flow of two immiscible liquids in the laminar‐turbulent regime. Curves through liquid‐liquid data available from three different sets of experiments, though being significantly displaced from the Lockhart‐Martinelli curves for gas‐liquid systems, represent the data with a maximum deviation of approxim

ISSN:0008-4034    

DOI:10.1002/cjce.5450440110

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

年代:1966

数据来源: WILEY