Optimization and Characterization of Facility Effects for a Low-Power Electron Cyclotron Resonance Magnetic Nozzle Thruster

The modelling, proper experimental testing techniques, and optimization of an electron cyclotron resonance magnetic nozzle thruster is investigated. A zero-dimensional model using spatially averaged quantities is constructed to predict thruster performance trends based a set of free model parameters. From these simulations, it is found that wall losses and magnetic nozzle efficiency are the key drivers of thruster performance. An overview of the thrust and input power measurement techniques is presented, including a rigorous uncertainty analysis for measured thrust and efficiency. The consequences of on-ground vacuum facility pressure and wall proximity are then investigated, and a model is constructed to extrapolate measurements taken with finite pressure to space-like environments. Finally, the setup and results of an optimization experiment seeking to improve thruster efficiency using custom input waveforms are presented. The waveforms investigated include single-frequency and two-frequency tuning and pulsed modulation. It is found that thruster performance is closely linked to input frequency for single-frequency tuning while two-frequency and pulsed modulation are not shown improve thruster efficiency beyond the single-frequency maxima for the powers and flow rates investigated.PhDAerospace EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/174254/1/bwachs_1.pd