## THERMAL SCIENCE

International Scientific Journal

### STABILITY OF TWO SUPERPOSED VISCOUS-VISCOELASTIC FLUIDS

**ABSTRACT**

The Rayleigh-Taylor instability of a Newtonian viscous fluid overlying a Rivlin-Ericksen viscoelastic fluid is considered. Upon application of normal mode technique, the dispersion relation is obtained. As in both Newtonian viscous-viscous fluids the system is stable in the potentially stable case and unstable in the potentially unstable case, this holds for the present problem also. The behavior of growth rates with respect to kinematic viscosity and kinematic viscoelasticity parameters are examined numerically and it is found that both kinematic viscosity and kinematic viscoelasticity have stabilizing effect.

**KEYWORDS**

PAPER SUBMITTED: 2005-03-05

PAPER REVISED: 2005-06-25

PAPER ACCEPTED: 2005-08-18

**THERMAL SCIENCE** YEAR

**2005**, VOLUME

**9**, ISSUE

**2**, PAGES [87 - 95]

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