Effect of Non-Uniform Temperature Gradient on the Onset of Rayleigh-Bénard Electro Convection in a Micropolar Fluid

Subbarama Pranesh, Riya Baby

Department of Mathematics, Christ University, Bangalore, India.

DOI: 10.4236/am.2012.35067                

Abstract

The effects of electric field and non-uniform basic temperature gradient on the onset of Rayleigh-Bénard convection in a micropolar fluid are studied using the Galerkin technique. The eigenvalues are obtained for free-free, rigid-free and rigid-rigid velocity boundary combinations and for isothermal and/or adiabatic temperature boundaries. The microrotation is assumed to vanish at the boundaries. A linear stability analysis is performed. The influence of various micropolar fluid parameters and electric Rayleigh number on the onset of convection has been analyzed. One linear and five non-uniform temperature profiles are considered and their comparative influence on onset is discussed.

Keywords

Micropolar Fluid; Rayleigh Number; Electro Convection; Non-Uniform Temperature Gradients; Galerkin Technique

Conflicts of Interest

The authors declare no conflicts of interest.

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