Rotating Brinkman–Lapwood Convection with Modulation

Transport in Porous Media (Impact Factor: 1.55). 01/2011; 88(3):369-383. DOI: 10.1007/s11242-011-9744-7

ABSTRACT The purpose of this article is to analyze, theoretically, the effect of modulation on rotating Brinkman–Lapwood convection,
i.e., buoyancy-driven convection in a sparse porous medium subjected to rotation. Darcy–Brinkman momentum equation with Coriolis
term has been used to describe the flow. The system is considered rotating about an axis with non-uniform rotation speed.
In particular, we assume that the rotation speed is varying sinusoidally with time. A linear stability analysis has been performed
to find the critical Rayleigh number in modulated case. The effect of modulated rotation speed is found to have a stabilizing
effect on the onset of convection for different values of modulation frequency and the other physical parameters involved.

KeywordsRotation speed modulation–Brinkman Model–Lapwood convection–Coriolis force–Taylor number–Vadasz number–Viscosity ratio

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