1D and quasi-2D numerical models of the cathode temperature in steady-state magnetoplasmadynamic thrusters

Abstract

Electrical thrusters have been developed for increased fuel efficiency of space flight compared to chemical thrusters. Chemical thrusters are limited by the chemical reaction energy in the propellants, whereas electrical thrusters have their own power supply unit to directly input energy into the propellant (i.e., a noble gas). Thus, they have better fuel efficiency. One type of electrical thruster that has potential for future interplanetary journeys is the magnetoplasmadynamic (MPD) thruster. However, the cathode-plasma interaction inside an MPD thruster is not fully understood owing to its complexity and nonlinearity. The objectives of this work were to improve on previous models and explain the interaction between the cathode and nearby plasma region (i.e., sheath) of an MPD thruster in the steady state. Numerical 1D and quasi-2D models were developed by using the explicit method to predict the cathode temperature profile in an MPD thruster. The numerical results were compared with experimental data for verification. The 1D and quasi-2D numerical models partially provide fundamental knowledge on the cathodeplasma interaction and can be used to predict the cathode temperature profile inside an MPD thruster for future design and development