Transient effects by pintle motion in cavitating venturi tube for throttled bipropellant thruster

Abstract

An experimental study was conducted to investigate the behavior of an H2O2/kerosene bipropellant thruster during throttling. The thruster used 90 wt% hydrogen peroxide, and thrust was controlled using a variable area cavitating venturi valve equipped with a linear motor translating a pintle in a venturi geometry. In particular, transient effects were compared for three settings of pintle motion. Transient effects impacting pressure, temperature, thrust, efficiency, and instability data were analyzed. The results show that even at low chamber pressure, ignition occurred due to throttling, and no instabilities were created by changing the throttling speed. On the contrary, transient movements affected the recorded pressure data, impacting the characteristic velocity and thrust. Finally, this study provided new insight into H2O2/kerosene bipropellant throttling for deep throttling missions. Moreover, using the results from this study, the precision of future control algorithms will be improved.