Instability of MHD couette flow of an electrically conducting fluid

Abstract

We study the electrically conducting fluid stability of magnetohydrodynamic flow between parallel plates by Chebyshev collocation method by applied transverse magnetic field. Temporal growth is obtained by the governing equations. The results show that the dominating factor is the change in shape of the undisturbed velocity profile caused by the magnetic field, which depends only on the Hartmann number. The stability equations is solved by QZ-algorithm to find the eigenvalue problem. The numerical calculation show that Magnetic field with particular magnitude destabilizes Couette flow while other magnitude stabilize the flow. It is also analyzed that Rec decreases rapidly to the minimum value for Hartmann number Ha greater than 3.887 and increases steadily from Hartmann number Ha (>5.559). It is observed that critical Reynolds number Rec is larger as Hartmann number decreases from Ha=3.887. The two critical Reynolds numbers in the elliptic curves are found for different values of Hartmann number.