摘要:

AbstractThe damping rates of free oscillations in U‐tube manometers were measured in water and aqueous solutions of Polyox WSR 301, Separan AP273 and a wetting agent (Aerosol OT). The manometers were made from flexible plastic (PVC) or glass tube. Small reductions of the linear damping constant by low concentrations of Polyox and Aerosol additives in the PVC tubes were attributed to a reduction in surface tension effects. All the additives increased the linear damping constants in both types of manometer, when used at larger concentrations. This was found to be due solely to increased solution viscosity.Large fractional reductions in damping due to Polyox in the PVC‐tube systemwere associated with the nonlinear oscillations in the final period of the decay. This effect has not yet been explai

ISSN:0008-4034    

DOI:10.1002/cjce.5450570601

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

年代:1979

数据来源: WILEY

摘要:

AbstractA study was made of the fall of a single drop of carbon tetrachloride through pure or contaminated water. Results are presented for the variations of the shape of the drop and of the frequency of oscillation with diameter and Teepol concentration. It has been found that presence of surface active agents, increases the deformation of drops but reduces the frequency of oscillations. The comparison between these experimental data and several relations has shown that no previous correlations of either the eccentricity or the frequency of oscillation are satisfactory when the system is contaminated by some surfactants.

ISSN:0008-4034    

DOI:10.1002/cjce.5450570602

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

年代:1979

数据来源: WILEY

摘要:

AbstractGas holdup and mechanical power consumption were measured in aerated aqueous nonelectrolyte and electrolyte systems. The experiments were performed in 0.4 m diameter cylindrical flat‐bottomed and hemispherical‐bottomed tanks. Standard six‐blade turbine (D/T = 0.225, 0.325, 0.45) and four‐blade paddle (D/T = 0.225, 0.325) were used over a wide range of gas sparging rate and power dissipation. A semiempirical correlation for holdup with dimensionless groups, i.e. impeller Weber number, aeration number and ratio of impeller diameter to tank diameter has been developed; however, this correlation did not fit the electrolyte solution data. The power consumption data of both the impeller types and tank bottom types were found to fit satisfactorily the Michel‐Miller correlation with 20%

ISSN:0008-4034    

DOI:10.1002/cjce.5450570603

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

年代:1979

数据来源: WILEY

摘要:

AbstractBitumens extracted from oil sand taken from the Athabasca and Cold Lake regions of Alberta were studied by use of a Mechanical Spectrometer. A heavy crude produced in the Lloydminster area was also studied. Viscosity and first normal stress difference were measured as well as viscoelastic functions. The bitumens are mildly non‐Newtonian in shear and viscoelastic. The behavior is qualitatively similar to that observed in residual asphalts, but it is suggested that the bitumen maltenes form a better solvent for the asphaltenes than in the case with the asphalts. Concentration of solvent, asphaltenes and dispersed water have strong effects on the viscosity. These results are interpreted in terms of molecular aggregatio

ISSN:0008-4034    

DOI:10.1002/cjce.5450570604

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

年代:1979

数据来源: WILEY

ISSN:0008-4034    

DOI:10.1002/cjce.5450570605

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

年代:1979

数据来源: WILEY

摘要:

AbstractThe two phase pressure driven flow in a circular pipe in which the interface occupies an arbitrary horizontal position has, as shown by earlier authors, an explicit analytical solution in which the velocities are expressed as Fourier integrals. Here this is used to express the volumetric fluxes of each fluid as one‐variable integrals whose values can be easily computed. The results agree with those obtained by Gemmell and Epstein by numerical integration of the differential equation

ISSN:0008-4034    

DOI:10.1002/cjce.5450570606

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

年代:1979

数据来源: WILEY

摘要:

AbstractThe use of stochastic models to predict chemical conversion in turbulent tubular reactors with separate but miscible reaction feed streams has been limited by the inefficiency of the computational processes. This is despite the advantages of the stochastic approach when compared to the more popular diffusional based techniques. Mathematic analysis of the stochastic process leading to direct algabraic representation of the stochastic model is presented which considerably reduces the computational time requirement of the stochastic approach.

ISSN:0008-4034    

DOI:10.1002/cjce.5450570607

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

年代:1979

数据来源: WILEY

摘要:

AbstractA steady heat transfer problem was analyzed as a conjugated problem between a fully‐established laminar flow and the duct wall, under two kinds of boundary conditions at the outer wall surface. The internal heat generation is described as a linear function of the fluid temperature.The influence of the heat conduction in the wall was found to be important for the case with small wall conductance under a boundary condition of the first kind, and also for the large wall‐conductance case under the second condition. Such influence is more significant for the case with an internal heat sou

ISSN:0008-4034    

DOI:10.1002/cjce.5450570608

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

年代:1979

数据来源: WILEY

摘要:

AbstractRates of absorption of CO2into water, a 0.2 mol/L NaOH solution and a 40 wt% glycerol solution with and without the interfacial turbulence caused by micro‐stirrers, made of a magnetic material, were measured with use of a stirred vessel with known gas‐liquid interfacial area. The effect of the interfacial turbulence on the rate of gas absorption was remarkable in the lower range of the bulk turbulence. The enhancement factors due to the interfacial turbulence were calculated with use of the age distribution function of the Danckwerts type and they agreed well with the experimental resu

ISSN:0008-4034    

DOI:10.1002/cjce.5450570609

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

年代:1979

数据来源: WILEY

摘要:

AbstractThe kinetic study of propylene oxidation to acrolein over a ferric molybdate catalyst has been performed on a differential reactor. Among models derived on the assumptions of Langmuir Hinshelwood kinetic rate or on Mars and Van Krevelen oxido‐reduction mechanism, a discrimination method has been realized. The discrimination leads on one hand to the conclusion that acrolein is obtained either from oxygen of the oxide lattice or from absorbed dissociated oxygen. On the other hand carbon dioxide is formed both by acrolein degradation and by a mechanism excluding dissociation of oxyge

ISSN:0008-4034    

DOI:10.1002/cjce.5450570610

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

年代:1979

数据来源: WILEY