Study on propellant utilization in pulsed plasma thrusters

Low efficiency can restrict the application of a pulsed plasma thruster. Low propellant utilization is one of the main reasons of this low efficiency. To improve pulsed plasma thruster efficiency, the influences of design parameters (capacitor initial voltage, electrode gap and electrode width) on the propellant utilization of a pulsed plasma thruster are studied. Because the propellant utilization of a pulsed plasma thruster is difficult to measure, a model that can simulate the ablation and ionization processes of a pulsed plasma thruster is established. Based on the model, the propellant utilizations under different working conditions of pulsed plasma thrusters are estimated. The results show that, the propellant utilization of a pulsed plasma thruster decreases as the capacitor initial voltage increases under a given capacitance and increases as the capacitor initial voltage increases under a given discharge energy. In addition, the propellant utilization is not affected by the electrode gap and increases as the electrode width increases. The simulation results are explained and analyzed. According to the analysis, the design parameters affect the propellant utilization of a pulsed plasma thruster by affecting the electric field intensity and the neutral gas density between the electrodes. The increase in propellant utilization may decrease the energy utilization in a pulsed plasma thruster. This study can provide references for the design of high-performance pulsed plasma thrusters.