Torque characteristics of spherical Couette flow of magnetic fluid

H. Yamaguchi - I. Kobori

Abstract
The transient behavior of torque characteritics for a spherical Couette flow of a magnetic fluid has been studied numerically, when a magnetic dipole field is applied to the system. The rotational Reynolds number associated with the inner sphere is verified together with three modes of spin-up. The numerical results indicate that a large overshoot of the torque {damping oscillation for low Reynolds numbers) appears when the inner sphere is spun-up within a very short period. Post spin-up behavior, which leads to the formation of Taylor-Gortler vortices at high Reynolds numbers, indicates that the formation time is greater than that of a non-magnetic field case and thus the stabilization of the flow by the magnetic field has been confirmed. Figs 5, refs 9.