Micro-multi-plasmajet array thruster for space propulsion applications

In this study, the characteristics of a 6 × 6 micro-multi-plasmajet array thruster were examined in vacuum. The discharge and thrust characteristics were examined experimentally. For the discharge operation, a stable and uniform plume from each nozzle element across an arrayed nozzle was observed at total nitrogen propellant mass flow rates ranging from 2.1 to 37.5 mg/s and total discharge currents ranging from 20 to 40 mA. Typical values of thrust, specific impulse, and thrust efficiency at a mass flow rate of 37.5 mg/s and an input power of 27 W were 39 mN, 107 s, and 0.33, respectively. Moreover, thrust performance of the 6 × 6 micro-multi-plasmajet array thruster was compared with a conventional 3 × 3 micro-multi-plasmajet array and micro single plasmajet thrusters. It was shown that the average thrusts per nozzle element of the 3 × 3 and 6 × 6 micro-multi-plasmajet array thrusters were two and three times higher, respectively, than the micro-single plasmajet thruster.