摘要:

This Brief Communication is devoted to a discussion of Orlov’s extension of the Mott‐Smith method to study the propagation of a shock wave in a moderately dense hard sphere gas. It is shown that, at least in the present form, the method is not compatible with the conservation of momentum and energy. ©1995 American Institute of Physics. 

ISSN:1070-6631    

DOI:10.1063/1.868536

出版商:AIP    

年代:1995

数据来源: AIP

摘要:

The effects of particles on the linear stability of an oscillatory two‐phase plane channel flow are examined for small Stokes numbers. The results in this note are valid for the condition that the dimensionless oscillation frequency is of the order of unity or smaller. The particles are found to have a destabilizing effect at all flow oscillation frequencies except in the high‐frequency region and the extent of the destabilization increases with increasing particle mass fraction. The critical Reynolds number for a gas–particle flow may be significantly changed by the flow oscillation. ©1995 American Institute of Physics.

ISSN:1070-6631    

DOI:10.1063/1.868537

出版商:AIP    

年代:1995

数据来源: AIP

摘要:

The mixing process in the formation of an axisymmetric vortex ring is analyzed by direct numerical simulation. After the initial phase, when the impulse is imparted to the fluid, the mixing increases linearly in time with a slope that is directly proportional to the vortex circulation (&Ggr;) and to reactants diffusivity to the power −1/3 (Pe−0.33). In addition, for reacting flows with equivalence ratio (s) different from 1, it has been found that assdecreases the mixing first decreases and then increases. An explanation for this behavior is given. ©1995 American Institute of Physics.

ISSN:1070-6631    

DOI:10.1063/1.868538

出版商:AIP    

年代:1995

数据来源: AIP

摘要:

In the present study, errors in using Taylor’s hypothesis to transform measurements obtained in a temporal (or phase) frame onto a spatial one were evaluated. For the first time, phase‐averaged (‘‘real’’) spanwiseandstreamwise vorticity data measured on a three‐dimensional grid were compared directly to those obtained using Taylor’s hypothesis. The results show that even the qualitative features of the spanwise and streamwise vorticity distributions given by the two techniques can be very different. This is particularly true in the region of the spanwise roller pairing. The phase‐averaged spanwise and streamwise peak vorticity levels given by Taylor’s hypothesis are typically lower (by up to 40%) compared to the real measurements. ©1995 American Institute of Physics.

ISSN:1070-6631    

DOI:10.1063/1.868539

出版商:AIP    

年代:1995

数据来源: AIP

ISSN:1070-6631    

DOI:10.1063/1.868783

出版商:AIP    

年代:1995

数据来源: AIP