A Similar Flow Between Two Rotating Disks in the Presence of a Magnetic Field

Abstract

A similarity solution is obtained for a flow between two rotating parallel disks which, at time t * are spaced a distance H (1 − αt *)1/2 apart and a magnetic field proportional to B0 (1 − αt *)−1/2 is applied perpendicular to the disks. Approximate analytic solutions are given and a numerical solution to the resulting nonlinear ordinary differential equations is presented. The effects of magnetic forces on the velocity profiles, the normal forces and the torques which the fluid exerts on the disks are studied. It is observed that by increasing the magnetic force a considerable increase in the load can be achieved. Also, the torques are more sensitive to changes in the squeeze Reynolds number than to changes in the rotation Reynolds number.