Transient one dimensional numerical simulation of magenetoplasmadynamic thrusters

Submitted to the Department of Aeronautics and Astronautics in partial fulfillment of the requirements for the degree of Master of Science in Aeronautics and Astronautics Magnetoplasmadynamic, or MPD, thrusters are a promising method of propulsion for a variety of different space missions. This research develops and analyzes a numerical simulation of a quasi one dimensional model for an MPD thruster. A finite difference scheme is used to integrate the fluid equations for each species and a magnetic field equation derived from Maxwell's laws. The model includes separate electron and heavy species temperatures, varying conductivity, varying ionization fraction, collisional energy transfer between heavy particles and electrons, averaged viscosity and ambipolar diffusion, and electron heat conduction. Both constant area and variable area channels are examined. The applied current in the cases studied ranges from 79.6 me h to 159me te Adpt for an inlet mass flow of 0.5 .~ The length of the thruster is 0.2 meters with a minimum interelectrode separation of 0.02 meters. It is shown that thermal equilibrium is not a valid assumption in a typical MPD thruster. It is also found that viscosity plays a significant role in determining thruster performance. Area variation is also found to have a significant effect on performance. Acknowledgements I owe much gratitude to many people. I want to thank my advisor, Prof. Manuel Martinez-Sanchez, who has always been available when I needed advice and guidance. He has shown much patience with my mistakes, whether computer errors or misspellings. I would also like to thank the graduate students with whom I work, who have provided both technical help and friendship. They have made coming to work everyday almost enjoyable. I would particularly like to thank Eric Sheppard, for his help with MPD and his taking the time to edit my thesis, and Rodger Biasca, for his help with numerical methods, fluids, computers, and Latex. On a more personal note, I would like to thank Joanne for all her encouragement and understanding. Finally, I would like to thank my parents, who have done so much for me for so long.