Performance Characterization of Simulated Regoliths and Space Debris to Investigate the In-Situ Resource Utilization Capabilities of a Pulsed Plasma Thruster System

by Michael Wennerstrom

Institution: University of Washington
Year: 2018
Keywords: Asteroid Mining; Electric Propulsion; In-Situ Resource Utilisation; Plasma; Pulsed Plasma Thruster; Space Debris; Aerospace engineering; Aeronautics and astronautics
Posted: 02/01/2018
Record ID: 2212819
Full text PDF: http://hdl.handle.net/1773/40827


A coaxial pulsed plasma thruster operating at 18 Joules per pulse was discharged over lunar regolith simulant, silica powder, powdered aluminum, and solid Polytetrafluoroethylene to evaluate their potential as minimally refined in-situ propellant resources on other planets or moons for electric propulsion. All the propellants ablated and their plumes were examined using high-speed imaging, spectroscopy, and a double Langmuir probe. Silica produced a greater spectral intensity than lunar regolith. Imaging revealed that micron sized radiating particles are ejected from the anode, cathode, and propellant surfaces with speeds of up to 60 m/s. The double Langmuir probe revealed that in-situ propellants may produce peak charge densities similar to PTFE. Slower populations of charged particles were observed after the initial discharge only in the powdered propellants. The probe also revealed a lower bound to the plasma exit velocity of 6.3 km/s for aluminum, 19.3 km/s for lunar simulant, 17.8 km/s for silicon dioxide, and 20.39 km/s for PTFE.Advisors/Committee Members: Winglee, Robert M (advisor).