Multi-dimensional kinetic simulations of instabilities and transport in EXB devices

Summary form only given. Various ExB devices such as Hall thrusters, helicon thrusters, Penning and magnetron discharges are subject to numerous instabilities that yield anomalous electron transport and affect operation of these devices. To understand the details of anomalous electron transport in ExB devices we have performed multi-dimensional kinetic simulations of plasma processes in a number of ExB discharges. Results of simulations are compared with experimental findings [1] as well as fluid simulations [2]. The LSP (Large-Scale Plasma) PIC-MCC code has been substantially modified to simulate several ExB configurations including Hall Thruster and Penning discharge [1]. To enable robust simulations of these discharges, we implemented a new electrostatic solver using the PETSc library interface; we added comprehensive collision models based on anisotropic scattering [3], implemented electron emission algorithms from the EDIPIC [4] code and modified the external electric circuit model. The customized code, PPPL-LSP, now successfully models low-temperature plasmas in multiple dimensions and can be run on hundreds of processor cores, with simulations resolving fast electron processes as well as reach steady state (on ion time scale) without scaling of cross sections or reducing ion mass. We have performed extensive verification and validation of the modified code. In particular, various instabilities in ExB devices were simulated for Penning and magnetron discharges. Initial 3D simulations of the cylindrical Hall thruster [5] were also performed.