Effect of Magnetic Field Dependent Viscosity on Darcy-Brinkman Ferroconvection with Second Sound

The problem of buoyancy-driven convection in a ferromagnetic fluid saturated porous medium with the Maxwell-Cattaneo law and MFD viscosity is investigated by method small perturbation. motion described using Brinkman model. It assumed that solid matrices are local thermal equilibrium. For simplified boundary conditions, eigenvalue solved exactly, closed form solutions for stationary instability obtained. Magnetic forces second sound were found to enhance beginning ferroconvection. However, ferroconvection hampered when parameters increased. results show inhibits Darcy-Brinkman stabilizing effect decreased magnetic Rayleigh number significant. Furthermore, it demonstrated oscillatory arises before instability, assuming Prandtl Cattaneo numbers sufficiently large.