Flexible Fuel Electron Source for Space Propulsion Systems

Busek and WPI propose to develop a cathode electron source for spacecraft ion drives that are fueled by a variety of reactive and semi-reactive molecular propellants. The cathode may be fueled by ASCENT (AFM-315e), iodine (I2), air (N2 + O2), carbon dioxide (CO2) as well as other substances. The proposed flexible fuel cathode is an extension of existing low current cathode technology that is presently being marketed for NASA, DoD, and commercial missions. The flexible fuel electron source would neutralize the ion beam created by a Hall effect Thruster or Gridded Ion Thruster.  Hall thrusters and gridded ion thrusters are forms of spacecraft electric propulsion (EP).  The exhaust velocity or specific impulse of these thrusters may be up to an order of magnitude higher than possible with a chemical rocket, greatly increasing spacecraft fuel efficiency. In Phase I Busek will establish requirements in cooperation with the government stake holder. WPI will take the lead in developing a global model of the electron source, which will be instrumental in scaling up the technology and adapting it to multiple propellants. The team will also develop a technology development plan and a Phase II work plan. Finally, Busek and WPI will document their results in a report.  In Phase II, Busek and WPI will develop and test a flexible fuel cathode at current levels up to 3 – 4 A, which is enough to enable a variety of single fuel small spacecraft EP systems.