Micro-multi-plasmajet array thruster for space propulsion applications

Thrust performance tests were conducted for an arrayed multi-plasmajet structure consisting of rectangular nozzle elements each with an exit height of 0.5 mm and length of 0.5 mm. To evaluate the thrust characteristics of the arrayed micro-multi-plasmajet, the thrust was measured using a calibrated cantilever-type thrust stand in vacuum. Using 3 × 3 nozzle elements, the micro-plasmajet array showed stable DC operation. Compared to conditions with cold-gas flow, the application of a DC discharge showed a significant improvement in thrust performance of at least 20% for thrust and specific impulse. Typical values achieved for thrust, specific impulse and thrust efficiency at an input power of 6.3 W were 8.5 mN, 77 s and 0.21, respectively.