Validation of an additively manufactured resistojet through experimental and computational analysis

This paper presents the first proof of concept validation of the STAR thruster prototype. The device contains an innovative multifunctional monolithic heat exchanger, enabled by metal additive manufacturing processes. A 316L stainless steel printed thruster is characterized through a combination of dry heating and wet firing tests. This includes verification testing with argon in both cold and hot firing mode, at a range of electrical power inputs. Thrust measurements range from 9.7 mN ± 0.16 mN–29.8 mN ± 0.16 mN, with a maximum measured specific impulse of 80.11 ± 1.49 s. Thrust performance is measured using a high-precision balance, and liquid-metal power transfer terminals to eliminate thermal drift. Highly coupled multiphysics computational models provide validation of the electro-thermal and thermo-fluidic characteristics of the prototype, including a prediction of the maximum propellant stagnation temperature and structural temperature, which were 649 °C and 854 °C. •Proof of concept validation of the Super-high Temperature Additive Resistojet.•SLM enabled a thin-wall concentric monolithic heat exchanger and resistive heater in 316L.•The prototype produced a specific impulse of 80.11 ± 1.49 s with Ar propellant.•Simulations suggest that the maximum structural temperature was of 854 °C.