摘要:

In [16], during an experiment designed to model the internal circulation of a forming droplet, secondary surface flows were observed on the droplet interface.

ISSN:0098-6445    

DOI:10.1080/00986448308940286

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

Self-sustained, isothermal oscillations in outlet species concentrations were observed under certain steady inlet conditions in the case of the CO—NO—O2—H2O reaction system on Pt/γAl2O3catalyst in a fixed-bed tubuiar reactor. The oscillations were mostly aperiodic, and for fixed inlet concentrations of the other species, they occurred in a rather narrow window of inlet oxygen concentrations near the stoichiometric point. The amplitude and frequency of these oscillations were affected by temperature and by the inlet concenlrations of CO and NO. Systemalic experiments, conducted to understand the cause of these oscillations, revealed that the catalyst aging procedure and the presence of water vapor induced the complex dynamic behavior observed in the CO—NO—O2—H2O system. The oscillations are explained qualitatively in terms of the competition among the various reactants for adsorption and subsequent reaction on the catalyst surface.

ISSN:0098-6445    

DOI:10.1080/00986448308940287

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

A systematic simulation study of dual composition control of distillation has been carried out in order to compare different decoupling strategies and contrast them with well-tuned SISO-controllers.

ISSN:0098-6445    

DOI:10.1080/00986448308940288

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

The flow of suspensions parallel to porous surfaces is typical to engineering and biological systems. In some cases the flow is associated with transfer of mass. This paper considers the effect of the presence of rigid particles near the porous boundary. The kinematic response of the particles to the viscous stresses imposed by the flowing fluid results in streamlines which penetrate the permeable boundary, thus providing a convective enhancement of the rate of transfer. This mechanism is totally absent with boundaries impermeable to flow. The general equations are developed and the important dimensionless parameters are defined. A particular example concerning linear shear flow past a catalytic boundary is evaluated.

ISSN:0098-6445    

DOI:10.1080/00986448308940289

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

On the basis of the model suggested in this paper an expression for the coefficient of mass transfer from a solid particle suspended in a turbulent flow of liquid β = Q.261ScL-3/4(EvL)1/4has been obtained theoretically. It is in good agreement with experimental data. The dissolution kinetics of particles is analytically described and a common procedure for calculating the dissolution of solids with arbitrary size distribution in stirred vessels has been developed on the basis of these results. The calculation results are compared with the experimental data obtained in vessels of different diameter with and without baffles.

ISSN:0098-6445    

DOI:10.1080/00986448308940290

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

ISSN:0098-6445    

DOI:10.1080/00986448308940291

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

A procedure for the systematic determination of feedforward control schemes for chemical processes is presented and an algorithm is derived. The proposed method makes use of the structural features of the process to be controlled and can be applied to linearized process models.

ISSN:0098-6445    

DOI:10.1080/00986448308940292

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

Porous media placed in the entrance of capillaries were found to reduce the pressure drop across the capillaries (▵Pc) by a factor of two or three for polystyrene. The reduction in ▵Pcwas found to be a function of the distance of the porous media from the capillary entrance, the type of porous media, the length of the capillary, and the rheological properties of the polymer melt. No significant reduction in ▵Pcwas observed for a polymer melt such as polyethyleneterephthalate (PET) which is nearly devoid of memory. The apparent shear rate for the onset of melt fracture was extended by a factor of three when polystyrene passed through the porous media before entering the capillary. No significant difference in die swell values was observed with the use of porous media in the entrance of the capillaries. The mechanism which accounts for these phenomena is believed to be associated with the break up of the entanglement network in the porous medium which temporarily changes the rheological properties of the polymer melt.

ISSN:0098-6445    

DOI:10.1080/00986448308940293

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

The interpretation of the signals generated by a double probe may be done by the three characteristic times method:

ISSN:0098-6445    

DOI:10.1080/00986448308940294

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor

摘要:

Reliable methods for the characterization of the surface properties and the wettability of small particles have not been available in the past. A novel technique, based on the behaviour of the lest particles at the solidification front of certain well defined solidifying melts (matrix materials) has been developed recently in our laboratory. This method was used to determine contact angles and surface tensions of coal particles in the range of 20-250 μm. Two types of bituminous and one type of subbituminous coal were tested using thymol, biphenyl, napthalene, salol and 2-phenyl phenol as matrix materials.

ISSN:0098-6445    

DOI:10.1080/00986448308940295

出版商:Taylor & Francis Group    

年代:1983

数据来源: Taylor