Modeling of Dynamic FRC Formation

We have developed a 2-D resistive MHD code, Lamy Ridge, to simulate the entire FRC formation process in Tri Alpha's C2 device, including initial formation, translation, merging and settling into equilibrium.~ Two FRC's can be created simultaneously, and then translated toward each other so that they merge into a single FRC.~ The code couples the external circuits around the formation tubes to the partially ionized plasma inside.~ Plasma and neutral gas are treated as two fluids.~ Dynamic and energetic equations, which take into account ionization and charge exchange, are solved in a time advance manner.~ The geometric shape of the vessel is specified by a set of inputs that defines the boundaries, which are handled by a cut-cell algorithm in the code.~ Multiple external circuits and field coils can be easily added, removed or relocated through individual inputs.~ The design of the code is modular and flexible so that it can be applied to future devices.~ The results of the code are in reasonable agreement with experimental measurements on the C2 device.