FIELD IONIZATION TEST CHAMBER FOR CARBON NANOTUBE–BASED MINIATURE ION THRUSTER APPLICATIONS - Video Portal
FIELD IONIZATION TEST CHAMBER FOR CARBON NANOTUBE–BASED MINIATURE ION THRUSTER APPLICATIONS
LT Bryan Crosby, USN
Abstract: Electric propulsion for micro and nano-satellites is an increasingly viable solution for station keeping and end-of-life operations. In particular, MEMS electrodes for use in a field ionization electric propulsion thruster are starting to show compelling evidence as a viable plasma generator electrode. This was determined by engineering a bell jar pressure chamber and a proof of concept field ionization electrode characterization fixture complete with an accelerator mesh grid, and a beam current data acquisition suite. The complete field ionization electrode characterization apparatus enables the user to view the generated ion plasma, collect beam current and enables future work to incorporate a thrust stand and a cathode/anode gap micrometer. Beam current collected from a series of experiments comparing angled-wall etched nozzles with and without CNT deposition showed a distinct improvement in maximum collected current. Mass utilization efficiency and specific impulse for a CNT electrode was found to be 0.31% and 17.5 seconds respectively at 560V. This is marginal in comparison to thrusters in industry; however, it shows a successful apparatus and test fixture proof of concept.