Research Papers: Porous Media

Vadasz Number Influence on Vibration in a Rotating Porous Layer Placed Far Away From the Axis of Rotation

[+] Author and Article Information
S. Govender

Generation Business Engineering, ESKOM Holdings Ltd., Maxwell Drive, Sunninghill, Johannesburg 2000, South Africa; School of Mechanical Engineering, University of Kwa-Zulu Natal, King George V Avenue, Durban 4001, South Africa

J. Heat Transfer 132(11), 112601 (Aug 13, 2010) (5 pages) doi:10.1115/1.4002036 History: Received April 09, 2010; Revised June 07, 2010; Published August 13, 2010; Online August 13, 2010

We consider vibration effects on the classical Rayleigh–Be’nard problem and the classical Vadasz (1994, “Stability of Free Convection in a Narrow Porous Layer Subject to Rotation,” Int. Commun. Heat Mass Transfer, 21, pp. 881–890) problem, which includes rotation of a vertical porous layer about the z-axis. In particular, we focus on the influence of the Vadasz number on vibration for small to moderate and large Vadasz numbers. For small to moderate Vadasz numbers, we develop an analogy between the Vadasz problem (Vadasz, 1994, “Stability of Free Convection in a Narrow Porous Layer Subject to Rotation,” Int. Commun. Heat Mass Transfer, 21, pp. 881–890) placed far away from the axis of rotation and classical Rayleigh–Be’nard problem, both of which include the effects of vibration. It is shown here that the stability criteria are identical to the Rayleigh–Be’nard problem with vibration when g=ω2X0. The analysis for the large Vadasz number scaling indicates that a frozen time approximation is appropriate where the effect of vibration is modeled as small variations in the Rayleigh number definition.

Copyright © 2010 by American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.



Grahic Jump Location
Figure 1

(a) The offset vertical rotating porous layer to vibration and (b) the horizontal porous layer subjected to gravity modulation




Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In