Comparison of Experimental and Computational Simulations Results of a Pulsed Plasma Accelerator IEPC-2005-008

High power pulsed plasma thrusters (PPT) contain regions of high density plasma in close contact with regions of vacuum that challenge accurate numerical simulations using current MHD codes. A new version of the GEMS code has been developed to provide a method to accurately calculate these regions of disparate density. The GEMS code now includes a full Maxwell equation solver capable of providing both wave and diffusion solutions, and comparisons with analytical solutions and MACH2 simulations are given to demonstrate its accuracy. In addition, numerical calculations using GEMS illustrate the importance of a solution technique that handles all regimes from ideal insulator to good conductor. A MACH2 simulation of a simple Marshall gun thruster demonstrates the need for multiple regime computations in high power pulsed plasma thrusters. A laboratory Marshall gun thruster was developed to provide an array of diagnostic measurements that can be compared with the numerical simulations. The prototype thruster has been tested and a collection of photographic images, laser interferometer data, Rogowski coil data, and B-dot probe data was acquired. These measurements will provide data to compare with MACH2 and GEMS simulations.