Effect of energy input on the discharge characteristics of a microcathode arc thruster

To explore the effect of energy input on the discharge characteristics of a micro cathode arc thruster, the relationships between the different input PPU voltages of the micro cathode arc thruster and the plume shape, arc characteristics, thruster propulsion performance, and working fluid ionization are characterized in this research. The results obtained using a high-speed camera indicate that the change in the thruster's energy input affects the plume contraction. Further, the results of spectroscopy and electrical testing analyses show that an increase in the thruster input voltage prolongates the arc duration, ionization rate of the arc, and degree of plume contraction. When the thruster is in a low input voltage state, the arc ionization rate primarily affects thrust-to-power ratio. However, when the thruster is in a high input voltage state, the degree of plume contraction primarily affects propulsion efficiency.