Novel fabrication method for a hot gas supersonic micro-thruster

A key element in the development of more capable nano- and pico-satellites is the development of high specific impulse micro-propulsion systems, which allow for more challenging space missions to be flown. One such system being developed at TU Delft is a micro-resistojet with a planar supersonic nozzle geometry. This is currently fabricated by means of silicon etching, which is unfortunately relatively slow and expensive. As a faster, more accessible alternative, wire electric discharge machining has been used here for creating the supersonic nozzle. This method was combined with COTS heaters and a metal foam heat exchanger to create a new micro-thruster. The thruster was tested in vacuum using nitrogen as propellant at temperatures up to 400 °C. Results showed similar thrust and specific impulse values as reported by others for a comparable silicon-based micro-thruster, thereby confirming the validity of the novel manufacturing method.
Aerospace Engineering