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

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.