Nonlinear Stability of Convection in a Thermally Modulated Anisotropic Porous Medium

Conditions corresponding to the unconditional stability
of convection in a mechanically anisotropic fluid saturated porous
medium of infinite horizontal extent are determined. The medium
is heated from below and its bounding surfaces are subjected to
temperature modulation which consists of a steady part and a
time periodic oscillating part. The Brinkman model is employed
in the momentum equation with the Bousinessq approximation.
The stability region is found for arbitrary values of modulational
frequency and amplitude using the energy method. Higher order
numerical computations are carried out to find critical boundaries
and subcritical instability regions more accurately.

Authors:

• M. Meenasaranya
• S. Saravanan

Keywords:

• Convection
• porous medium
• anisotropy
• temperature modulation
• nonlinear stability.

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