Axisymmetric helical magnetorotational instability in a Taylor-Couette flow with sufficiently large positive shear

Abstract

The range of parameters is explored for the axisymmetric helical magnetorotational instability in a Taylor-Couette flow with high enough positive shear. The magnetic Prandtl number has a wide range from 10−6 to 100. The ratio of the azimuthal magnetic field to the axial magnetic field β is equal to 20, 50, 70 and 100. In different parameters, the stability curves are computed and shown in the plane for the Lundquist numbers S on the x-axis and for the magnetic Reynolds numbers Rm on the y-axis. The computed results can help find or avoid the instability in the corresponding flows. Figs 6, Refs 29.