Pressurized Xenon Propellant Management System for the CubeSat Ambipolar Thruster

The CubeSat Ambipolar Thruster (CAT) is nominally designed to operate on inert gas propellants with a target ΔV capability of greater than 1000 m/s. The design process for a prototype pressurized inert gas propellant feed system capable of storing enough propellant to meet this target and of delivering propellant at the flow rates of 5 15 sccm of xenon and pressures of 1 10 mbar required by CAT for an on-orbit technology demonstration mission is presented. To reduce cost and shorten development cycles, commercial-off-theshelf (COTS) components were used and rapid manufacturing techniques were leveraged. The laser-sintered titanium propellant tank was nominally designed to store propellant at pressures up to 100 bar to exploit the supercriticality and enhanced density of xenon. The prototype tank was hydrostatically tested to 130 bar, partially validating the use of laser-sintering. The piping train comprised a three-stage pressure regulator, a low-power valve, and a standard-sized static orifice. To deliver xenon propellant at the flow rates and pressures required by CAT, a COTS orifice diameter of 40 μm was selected for integration into an engineering unit of the satellite for laboratory testing. The volume of the entire, non-optimal propulsion subsystem package is ≤ 2U, with the propellant tank as the primary component that can be scaled to meet the specific mission requirements, and the propellant management system mass is ∼ 500 g. A discussion of possible methods of optimizing the mass and volume of the propellant management system is included. Using a low thrust orbit propagator it was shown that a 3U CubeSat equipped with CAT and this propellant management system could execute a variety of orbital maneuvers, including GEO insertion, Earth escape, and orbit circularization.