Catalyst-Free, Highly-Throttleable, Electric Propulsion Thruster

The future of monopropellant thrusters is moving towards high performance green propellants based on hydroxyammonium nitrate (HAN) and ammonium dinitramide (ADN). Ideally, a multi mode propulsion system will include a higher specific impulse thruster for maneuvers that require propellant conservation to complement a higher thrust chemical thruster, with both thrusters utilizing the same propellant. We propose to develop an electric thruster that operates on almost any monopropellant, including hydrazine for near term missions, while maintaining high performance over a wide range of operation. The key to success is the elimination of the catalyst bed, shown to be a hindrance for both high performance (HAN, ADN) chemical thrusters and electric propulsion. Elimination of the cat bed should also increase the throttling capabilities of the electric propulsion engine. This catalyst-free thruster will also overcome thermal and life issues of the catalyst bed and allow for utilization of almost any propellant imagined. In Phase I we will demonstrate the operation of our electrically catalyzed thruster operating on a selected monopropellant. Key technologies include the liquid propellant injector and thruster starting. Pressure and temperature measurements will prove the success of our design.