Measurement and diagnosis of ion thruster plume using a mixed working medium

Abstract The use of CO 2 to partially replace traditional propellants in electric propulsion (EP) offers cost-effectiveness and good performance. This study investigates the impact of CO 2 /Xe mixing ratios on Kaufman ion thruster plume characteristics through experiments. The plume characteristics of a Kaufman ion thruster are studied under different mixing flow rates and anode currents, while the underlying mechanisms of plasma formation in the mixed-medium thruster are explored. Results show that increasing the anode current and Xe flow rate promotes plasma generation, reduces electron temperature, and increases ion density. The addition of small amounts of CO 2 in the discharge chamber enhances thruster performance by reducing beam divergence, increasing ion density, and minimizing charge-exchange (CEX) ion reflux. However, further increases in CO 2 flow rate leads to deterioration in plume characteristics. An optimal CO 2 /Xe mixture ratio of 1:1 under the tested conditions is demonstrated, which yielded superior beam performance characteristics.