A spherical couette experiment to observe inductionless MHD instabilities at medium Reynolds numbers

A liquid metal (GaInSn) spherical Couette flow is being carried out at the Helmholtz-Zentrum in Dresden-Rossendorf to explore a region of Reynolds-Hartmann space in which numerical simulations [1, 2] show hydrodynamically unstable and magnetohydrodynamically unstable regions separated by an isthmus of stability. The region is of further interest because these (inductionless) instabilities have similar signatures to the instabilities found in a larger scale, less thoroughly diagnosed experiment, that were reported as the (induction dependent) Magnetorotational instabiliity (MRI) [3].

[1] Hollerbach, R. (2009). Non-axisymmetric instabilities in magnetic spherical Couette flow. Proc. R. Soc. London A, 465:2003–2013.
[2] Travnikov, V.; Eckert, K.; and Odenbach, S.: (2011). Influence of an axial magnetic field on the stability of spherical Couette flows with different gap widths. Acta Mech, 219:255–268.
[3] Sisan, D. R.; Mujica, N.; Tillotson, W. A.; Huang, Y.-M.; Dorland, W.; Hassam, A. B.; Antonsen, T. M.; and Lathrop, D. P.: (2004). Experimental Observation and Characterization of the Magnetorotational Instability. Phys. Rev. Lett., 93(11):114502.