PPPS-2013: Ion-current FRC using a modified MHD model

Abstract

Summary form only given. In the standard MHD formulation the effects of finite gyroradius and gyroperiod are usually absent. To include these effects we have modified MACH2, a 2D MHD code, and then simulated recent experiments performed at Tri Alpha Energy, Inc.1 and the University of CA, Irvine.2 In the experiments an azimuthal-electric field is produced by a flux coil that is co-axially located with the plasma.3 In the presence of a pre-formed, magnetized plasma the Eθ field induces a diamagnetic-plasma current that reverses the applied-magnetic field, forming a FRC. The simulations suggest that the azimuthal current is due initially to ion flow, until the FRC is formed, when the electrons are free to accelerate in the field-free region, near the magnetic-null. For the same set of initial parameters there is good agreement between the simulations and the experiments.