## THERMAL SCIENCE

International Scientific Journal

### RAYLEIGH TAYLOR INSTABILITY IN DUSTY MAGNETIZED FLUIDS WITH SURFACE TENSION FLOWING THROUGH POROUS MEDIUM

**ABSTRACT**

In this paper we investigate the effect of surface tension on hydromagnetic Rayleigh-Taylor (R-T) instability of two incompressible superimposed fluids in a porous medium with suspended dust particles immersed in a uniform horizontal magnetic field. The relevant linearized perturbation equations have been solved using normal mode technique and the dispersion relation is derived analytically for the considered system. The dispersion relation is influenced by the simultaneous presence of medium porosity, suspended dust particles, permeability, magnetic field and surface tension. The onset criteria of R-T stability and instability are obtained and discussed. The growth rate of R-T instability is calculated numerically and is affected by the simultaneous presence of surface tension and magnetic field. The effects of various parameters on the growth rate of the R-T instability are discussed.

**KEYWORDS**

PAPER SUBMITTED: 2013-10-27

PAPER REVISED: 2014-02-27

PAPER ACCEPTED: 2014-03-22

PUBLISHED ONLINE: 2014-04-05

**THERMAL SCIENCE** YEAR

**2016**, VOLUME

**20**, ISSUE

**Issue 1**, PAGES [119 - 130]

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