Resistive MHD Evolution of Shaped RFP Equilibria

Computational modeling of the resistive MHD evolution of reverse-field-pinch (RFP) plasmas with boundary shaping is undertaken. The VMEC code obtains equilibria that are similar to quasi-single helicity (QSH) states in an RFP with a helical axis and a symmetric boundary [J.D. Hanson, et al., Nuclear Fusion 53, 083016 (2013)]. Previous work has shown that axisymmetric boundary shaping affects whether an axisymmetric or QSH equilibrium is obtained in VMEC. In this work these equilibria are used as initial conditions for the NIMROD code [C.R. Sovinec, et al., Phys. Plasmas 10, 1727 (20030]. Particular attention will be paid to the evolution of global tearing modes in both axisymmetric and helical equilibria.