An experimental study of performance and thrust control characteristics of N2O-based rotating gliding arc thrusters

Abstract

The recent growth of the launch vehicle market has made orbit access more affordable and expanded the range of mission types and orbits, requiring customized propulsion systems with high flexibility. In this study, a novel electro-chemical thruster with an N₂O monopropellant and AC-powered rotating gliding arc (RGA) was proposed. Furthermore, the thruster propulsion performance and thrust control characteristics as a function of the N₂O flow rate and applied power were systematically analyzed. The RGA thruster rotated the arc by using the swirl flow and repeated AC arc discharge. The thruster can maintain a stable discharge at maximum chamber pressures of up to approximately seven times the atmospheric pressure. Additionally, the thruster could achieve instantaneous N₂O decomposition without the use of a catalyst, and the remaining electrical power after decomposition could be used to heat products, resulting in enhanced performance. Under all experimental conditions, the characteristic velocity efficiency exceeded 100 %, with a maximum efficiency of 136.5 %. Additionally, the concept of effective temperature was introduced to simplify performance predictions for the RGA thruster. The effective gas temperature under these conditions was estimated to be 3410 K, and the vacuum-specific impulse was calculated to be 278.9 s, which was higher than the specific impulse of 202.8 s for chemically decomposed N₂O. Thrust control experiments confirmed that the N₂O flow rate and applied power could be independently controlled, enabling precise target thrust generation. This result revealed that both continuous and discrete thrust control based on impulse bits are viable and satisfy the high maneuverability and flexibility demands of space missions.