Study of Surface Instability of Kelvin-Helmholtz Type in a Fluid Layer Bounded above by a Porous Layer and below by a Rigid Surface

Nanjundappa Rudraiah, Krishna Basappa Chavaraddi, Inapura Siddagangaiah Shivakumara, Bangalore Mahadevaiah Shankar

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DOI: 10.4236/wjm.2011.16033                

Abstract

The surface instability of Kelvin-Helmholtz type bounded above by a porous layer and below by a rigid surface is investigated using linear stability analysis. Here we adopt the theory based on electrohydrodynamic as well as Stokes and lubrication approximations. We replace the effect of boundary layer with Beavers and Joseph slip condition. Here we have studied the combined effect of electric and magnetic fields on Kelvin-Helmholtz instability (KHI) in a fluid layer bounded above by a porous layer and below by a rigid surface. The dispersion relation is obtained using suitable boundary and surface conditions and results are depicted graphically. Also the ratio Gm is numerically computed for different values of We and M given in the Table 1. From this it is clear that the combined effect of electric and magnetic fields with porous layer are more effective than the effect of compressibility in reducing the growth rate of RTI. Also, these results shows that with a proper choice of magnetic field it is possible to control the growth rate of Electrohydrody-namic KHI (EKHI) and hence can be restored the symmetry of IFE target.

Keywords

Electrohydrodynamics, KHI, Magnetic Field, BJ-Slip Condition, Porous Layer

Conflicts of Interest

The authors declare no conflicts of interest.

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