Hall current and inlet disturbances in constant area channel flows

Abstract

The problem considered is that of obtaining the fluid flow fields introduced within an electromagnetic accelerator, by the off-axis of the Lorentz force created when a component of the electric current exists. In addition, the growth or decay of inlet disturbances is investigated. In this paper a perturbation solution for the fluid properties is obtained. The reference flow about which the perturbation is taken is a modified channel-flow solution which becomes exact as the ratio of channel height to channel length approaches zero. Several example solutions are computed, all but one of which lead to closed form expressions for the dependent variables in terms of the velocity of the imposed channel flow. The solutions indicate that for values of the Hall parameter near or greater than unity, the validity of the channel-flow solutions will be questioned in some cases of high electromagnetic loading, unless the channel width is kept very small. The results for the behavior of inlet disturbances show that in all cases considered such disturbances grow to some extent downstream.