摘要:

AbstractResidual oil was obtained by waterflooding, under water‐wet conditions, in unconsolidated packs of glass spheres at low capillary numbers. Trapped oil blobs were mobilized in a sequence of decreasing size with subsequent increases in capillary number. The larger blobs, which extend over many adjacent pores, fission repeatedly upon mobilization and the smaller daughter blobs are restranded. There is negligible oil production until the blob population has been reduced to single pore blobs (singlets).Thus, the critical capillary number for mobilization of significant amounts of oil in unconsolidated bead packs is not related to the original blob size population, but rather to the conditions necessary for mobilization of singlet

ISSN:0008-4034    

DOI:10.1002/cjce.5450630401

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

年代:1985

数据来源: WILEY

摘要:

AbstractThe dip coating operation with shear‐thinning fluids is simulated by the Augmented Lagrangian Method coupled to a finite element discretization. Numerical predictions of coating thickness and meniscus shape compared with experimental data exhibit a very poor agreement. The discrepancy of results is explained by the inadequacy of shear‐thinning rheological models to describe the dynamics of the coating process in a non‐purely viscometric situation and also by the presence of a weak level of elasticity in the fluids

ISSN:0008-4034    

DOI:10.1002/cjce.5450630402

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

年代:1985

数据来源: WILEY

摘要:

AbstractA new analysis has been developed for the turbulent flow of non‐Newtonian fluids. Based on enhanced viscosity effects at the small time and length scales of the dissipative micro‐eddies, the analysis predicts a thickening of the viscous sub‐layer tending to increase throughput velocity and thus promoting drag reduction. The required flow parameters can be determined directly from rheograms, without employing correlations based on pipe‐flow data. The results give good descriptions of flows of fluids with both power‐law and Bingham behaviour and explain a number of peculiarities of s

ISSN:0008-4034    

DOI:10.1002/cjce.5450630403

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

年代:1985

数据来源: WILEY

摘要:

AbstractNew experimental data on the flow patterns of condensing steam inside horizontal tubes of 13.4 and 25.3‐mm i.d. are presented and discussed. Comparisons with flow pattern maps of adiabatic (gas‐liquid) and condensing flows, as well as individual transition correlations, resulted in good agreements at the mist‐annular and annular‐wavy transitions. All of the horizontal flow pattern correlations tested failed in reasonably predicting the wavy‐slug transition while the results of gas‐liquid flow in upwardly inclined tubes appear to provide some explanation of the trend at this

ISSN:0008-4034    

DOI:10.1002/cjce.5450630404

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

年代:1985

数据来源: WILEY

摘要:

AbstractA study has been made of the wall to bed heat transfer in three‐phase fluidized beds with cocurrent upflow of the gas and the liquid, the liquid being the continuous phase. The experiments were done using five different liquids (tetra‐chloroethene, cyclohexane, kerosene, gas oil, water), three different kinds of particles (glass beads, porous alumina spheres and cylinders) at liquid velocities below 30 mm/s and gas velocities from 10 to 150 mm/s. The phenomena observed with a foaming liquid are described. Different literature correlations proved to be non‐applicable at the velocities used in this work; moreover, they are not able to take into account the influence of the nature of the liquid. Therefore, a new correlation which fits well our results is proposed. The areas requiring further investigation before a safe prediction of the wall heat transfer coefficient in three phase fluidized beds can be possible are det

ISSN:0008-4034    

DOI:10.1002/cjce.5450630405

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

年代:1985

数据来源: WILEY

摘要:

AbstractTheoretical and experimental investigations have been carried out for the mass transfer to an internally circulating drop forming in a continuously pulsating gas‐phase. Enhancement in mass transfer rate of about 200% has been achieved by increased internal circulation within the large‐sized drop during its formation, through pulsations in the gas‐stream. Effects of pulsation parameters on the overall mass transfer rate have been investigated. The experimental and computed data have also been compared for both the cases of physical absorption and absorption accompanied by fast, irreversible pseudo‐first order chemical reaction. Data show a good agreement for the two systems studied, the agreement being particularly good for the reacting

ISSN:0008-4034    

DOI:10.1002/cjce.5450630406

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

年代:1985

数据来源: WILEY

摘要:

AbstractHydrogen sulfide/water mixtures are frequently encountered in the petrochemical and heavy water industries. Such mixtures exhibit an inherent foaminess when operating close to the liquefaction pressure of H2S. This can cause severe problems in fluid handling equipment.Some nonionic surfactants are effective antifoams for these mixtures. The antifoam action is due to surfactant micelle formation which is enhanced by the presence of H2S through a “salting out” mechanism. The pressure at which a particular surfactant becomes an antifoam can be predicted from the hydrophobicity of the surfactant molecule. Such understanding could be applied to control foaming in other syst

ISSN:0008-4034    

DOI:10.1002/cjce.5450630407

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

年代:1985

数据来源: WILEY

摘要:

AbstractThis paper reports on the optimum range of rotor speeds for the operation of Rotating Disc Contactors (RDC). New information based on experimental investigations is presented regarding the existence of a second critical rotor speed which divides the varying characteristic velocity region into rapidly varying and gradually varying characteristic velocity regions of the dispersed phase droplets. New modifications to the reported generalised correlations for the prediction of characteristic velocity at all rotor speeds under conditions of no solute transfer as well as solute transfer between dispersed and continuous phases are suggested.

ISSN:0008-4034    

DOI:10.1002/cjce.5450630408

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

年代:1985

数据来源: WILEY

摘要:

AbstractStatic sedimentation experiments on coal‐#2 oil and coal‐water slurries, wet ground in a Szego mill, were conducted. These slurries contain more flaky particles as compared to those conventionally ground.Concentration and size distribution of the coal, diameter and height of the settling columns and settling time were the independent variables. Coal concentration and particle size distribution along the columns, and settling rates were measured.Despite their particle shape differences, these slurries were similar to others in terms of settling stability due to particle flocculat

ISSN:0008-4034    

DOI:10.1002/cjce.5450630409

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

年代:1985

数据来源: WILEY

摘要:

AbstractSpheres were produced from an iron‐ore concentrate by balling and subsequent shaping, and cylinders were cut from these spheres. Experimental data are presented, correlating the factorL/D2for the spheres with the failure stress of the cylinders. The latter was measured by the diametral compression (Brazilian) test.The results confirm the direct proportionality between the two, but only above a minimum level of agglomerate matrix strength. At less than 120 kPa the relationship may become complex. A qualitative explanation is offered in terms of the stress‐deformation behaviour of the spheres and cylind

ISSN:0008-4034    

DOI:10.1002/cjce.5450630410

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

年代:1985

数据来源: WILEY