The effect of easily ionized elements Na and K on the performance of pulsed plasma thruster using water propellant

Abstract

In view of the low thrust power ratio caused by the high resistance of pulsed plasma thruster using water propellant, the paper argues that the easily ionized elements Na and K with low ionic potentials are added in the water propellant to improve its performance. The measurement of the discharging current and plasma emission spectrographic analysis prove the improvement. The experiments show that the elements Na and K have certain effect on the improvement of the performance of pulsed plasma thruster: In comparison with water propellant, the NaCl and KCl water propellant has a lower total resistance and a higher ratio of thruster power and specific impulse, and the NaCl water propellant has a slightly stronger effect on pulsed plasma thruster than the KCl. The plasma emission spectrographic analysis is in consistent with the experiment of measuring the discharging current: The elements Na and K can intensify the plasma emission spectrographic signal.