Enhance of combustion efficiency of the hydroxyl ammonium nitrate (HAN)-based green monopropellant is an important topic for improving the capability of green propellant reaction control system (RCS) to achieve practical use. This paper conducts the atomization of HAN-based monopropellant SHP163 by the effect of flashing or flash atomization. Flashing is the atomization method using the pressure difference between the saturation pressure of a liquid and the ambient pressure. This paper reports the result of the injection test of SHP163 in different ambient pressures from atmospheric to near-vacuum and the catalytic thruster combustion test of SHP163 in two different pressures, atmospheric and near vacuum, and describes the effect of the flashing of green propellant for its catalytic combustion efficiency.
