ISSN:0001-1541    

DOI:10.1002/aic.690120202

出版商:American Institute of Chemical Engineers    

年代:1966

数据来源: WILEY

ISSN:0001-1541    

DOI:10.1002/aic.690120203

出版商:American Institute of Chemical Engineers    

年代:1966

数据来源: WILEY

摘要:

AbstractAn analytical study was made of the temperature and composition distribution and heat transfer characteristics for a reacting fluid in a tube. The reaction was assumed to be first order and irreversible and the flow to be laminar.The results, which consisted of radial and axial profiles of temperature, composition, and Nusselt number could be expressed in terms of four parameters. The gradient of radial composition was usually sufficient to judge the effect of reaction on the heat transfer coefficient. Owing to residence time and temperature effects, the Nusselt number even for an exothermic reaction was usually greater than that for an inert system. For endothermic cases, the energy flux due to diffusion increases the total energy flow, and the Nusselt number may be several fold that in the corresponding nonreactive system.For certain values of the parameters the radial temperature and composition profiles showed maxima and minima between the wall and center of the tube. At these conditions the direction of the flow of energy due to diffusion could not explain the increase in Nusselt number.

ISSN:0001-1541    

DOI:10.1002/aic.690120204

出版商:American Institute of Chemical Engineers    

年代:1966

数据来源: WILEY

摘要:

AbstractTurbulent and transitional flow heat transfer correlations for non‐Newtonian fluids are presented. By means of an extension of the Reichardt‐Metzner‐Friend correlation to nonisothermal flow, and a new definition of Prandtl number to account for deviations from Newtonian behavior, turbulent flow data are correlated to a standard deviation of 14.8%. By means of a normalizing procedure, data for the complex case of transitional flow heat transfer to non‐Newtonian fluids are correlated to a standard deviation of 17.7%. At the transition region boundaries, the correlation is consistent with laminar and turbulent flow correlations. A basic similarity in the Newtonian and non‐Newtonian heat transfer mechanisms is

ISSN:0001-1541    

DOI:10.1002/aic.690120205

出版商:American Institute of Chemical Engineers    

年代:1966

数据来源: WILEY

摘要:

AbstractAnalysis of the equations describing the instantaneous vapor and liquid flow through the holes of perforated distillation plates at low loads shows that periodic and stable pressure oscillations will always be set up between plates. These oscillations are expected to have amplitudes of the order of 0.1 in. of water and frequencies of a few cycles per second, values which are in accord with observation and which may be used as the basis for a model from which the seal point of the plates may be predicted.

ISSN:0001-1541    

DOI:10.1002/aic.690120206

出版商:American Institute of Chemical Engineers    

年代:1966

数据来源: WILEY

摘要:

AbstractFilm boiling above a horizontal surface has been investigated theoretically and experimentally at standard gravity and 1 atm. Theoretical film boiling results for conventional fluids have been extended, on the basis of interfacial instability due to gravity, to include liquefied gases properties, such as low viscosity and small surface tension. In the experiments, primarily ordinary liquid helium I has been studied to extend the range of the film boiling Rayleigh numbers (based upon Laplace's reference length) from about 107(reported for room temperature liquids) to values of the order of magnitude unity. The heat transfer data taken at surface excess temperatures ΔT(above the boiling point) between 80° and 300°K. have been correlated with a theoretical model which presumes the absence of any scaling length (Laplace length) associated with surface tension. At low ΔTthe experimental results have been found to agree with a model which presumes a negligible influence of a scaling length due to surface tension and absence of detectable viscosity effe

ISSN:0001-1541    

DOI:10.1002/aic.690120207

出版商:American Institute of Chemical Engineers    

年代:1966

数据来源: WILEY

摘要:

AbstractAn observation of the properties of bulk matter necessarily omits many details of the motion of the particles which comprise that matter. If a communication regarding the observation is to be consistent, it must conform to certain rules which follow from the theory of information. An analysis of the problem of deciding upon a consistent encoding for such observations leads, as a unique result, to the concepts and equations of classical thermodynamics. The information‐theory analysis of this problem also leads to a better understanding of the basis for the “laws” of thermodyn

ISSN:0001-1541    

DOI:10.1002/aic.690120208

出版商:American Institute of Chemical Engineers    

年代:1966

数据来源: WILEY

摘要:

AbstractThe influence of small surface waves on mass transfer from pure gases into water has been investigated. Small amplitude progressive two‐dimensional waves were mechanically generated at the liquid surface for the wave studies. Control experiments with nonwaved surfaces were also conducted. An effective diffusivity was used to correlate the data. Marked increases in mass transfer over that predicted by molecular diffusion for the no‐wave control runs are attributed to natural convection motions, and are probably caused by density and surface tension variati

ISSN:0001-1541    

DOI:10.1002/aic.690120209

出版商:American Institute of Chemical Engineers    

年代:1966

数据来源: WILEY

摘要:

AbstractInstantaneous mass transfer coefficients were obtained for the absorption of carbon dioxide bubbles rising in an aqueous solution of sodium carboxymethylcellulose. The rheological character of the solutions was well described by the Ellis model.Mass transfer coefficients were high initially but trailed off rapidly with bubble age. Exceptions were found at specific diameters where the bubble shape went through a transition. At about 0.2 cm. a transition from ellipsoidal to a sphere shape occurred, which has also been observed in Newtonian fluids. At a larger diameter, however, the non‐Newtonian fluid showed a shape change from a spherical “cap” to a “top” shape and finally to an ellipsoid. A sudden increase of mass transfer coefficient accompanied each shape transition.Drag coefficient data were correlated successfully with a new Reynolds number. The Newtonian and power law portion of the Ellis model each contributed a component to the Reynolds number, which, when added together, correlated drag data for the bubbles as well as for glass spheres.Attempts to account for transition shape changes and bubble tailing in the non‐Newtonian fluid and their effects on bubble mass transfer a

ISSN:0001-1541    

DOI:10.1002/aic.690120210

出版商:American Institute of Chemical Engineers    

年代:1966

数据来源: WILEY

摘要:

AbstractRates of oxidation of hydrogen chloride (the Deacon process) were measured in a recycling reactor with chromic oxide catalysts. The temperatures were 325° to 355°C., and a wide range of reactant compositions was used. The reverse reaction was also explored at 355° to 370°C. The experimentation was carefully tested to be sure that the construction material did not affect the results and that diffusional effects were absent.An empirical equation is described which correlates well the rates of oxidation and fits the original observed data. It is capable of predicting reasonably well some of the observed rates of the reverse react

ISSN:0001-1541    

DOI:10.1002/aic.690120211

出版商:American Institute of Chemical Engineers    

年代:1966

数据来源: WILEY