A steady-state, applied-field, rectangular magnetoplasmadynamics (MPD) thruster with permanent magnets has been developed. The thrust and discharge voltage were measured by varying propellant mass flow rates, discharge current and inter-electrode distance. Argon was used as the basic propellant. The effective energy consumption rates were evaluated from the effective exhaust velocity and discharge voltage characteristics. The discharge current distribution was the key to improve the thrust performance. When mixing hydrogen to the propellant of an equal volume flow rate, the discharge current distribution shifted downstream in the discharge channel and the thrust increased to 1.7 times of that with an equal total volume flow rate only of argon.
2015 The Japan Society for Aeronautical and Space Sciences