Convective instability of magnetic fluids under alternating magnetic fields

Abstract

A theoretical investigation of the convective instability problem in the thin horizontal layer of a magnetic fluid heated from below and under alternating magnetic fields is carried out. Both the quasistationary model and the model with internal rotation with vortex viscosity are considered. Floquet theory is used for discussing the existence and stability boundaries of the differential equations with periodic coefficients. The Chebyshev pseudospectral method is employed to discretize the partial differential equation, and QZ algorithm is used for solving the eigenvalue problem. For quasistationary model, both free-free and rigid-rigid boundary cases are considered, whereas for the model with internal rotation only rigid-rigid boundary condition is studied. The effect of frequency variations on the stability are considered in all the cases.