Investigation of interior ballistics and performance analysis of hydro-reactive motors

This paper deals with interior ballistics of hydro-reactive motors. The propellant consists of water as the main oxidizer and the fuel rich pyrotechnic as a solid fuel. The effects of water on the propulsive characteristics of this propellant are investigated. It is shown that raising the amount of water increases the pressure and thrust as well as specific impulse. An experimental study has been conducted in order to approve the feature of the hydro-reactive propulsion systems. A binary mixture of magnesium and sodium nitrate powders with mass fractions of 0.75 and 0.25, respectively, is selected as a solid fuel. Three tests have been performed at different levels of water mass flow rates. The data were reduced from the tests and average values of characteristics were extracted. The results confirm the predicted trend of the effects of water on the behavior of propulsive characteristics. The specific impulse of about 400 s has been achieved at chamber pressure of about 22 bar and water mass ratio of 0.74. It is expected that introducing higher values of water mass fractions increases the specific impulse. The results show that the motor behaves with more stability at this condition.