2.5 kN pump-pressure pintle engine ignition experiment in different loading cases

Advanced technology of motors and batteries has stimulated the application of the emerging electric pump in the liquid propulsion systems. However, the coupling characteristics between the electric pump and the pintle injector with high momentum ratio are not clear. In this study, suitable approaches were applied to conduct the ignition experiment that the hydrogen peroxide was catalyzed in full flow with kerosene in different cases. In the experiment, the electric pumps were used to pressurize the hydrogen peroxide and kerosene respectively. The experiment results showed that, the catalytic process would be realized between 1.0 s and 2.0 s in different cases while the ignition process could be reached between 0.1 s and 0.2 s, which was mainly caused by the overshoot between 15% and 30% in the catalytic process. When the injection valve remained closed after the expected speed was reached, the outlet pressure of electric pump would be subject to vibration. However, the low-frequency vibration predominated from 12 Hz to 31 Hz. After the injection valve opened, the pressure vibration of the kerosene electric pump was between 0.15 MPa and 0.8 MPa. As the load dropped, the pressure vibration would obviously escalate. Each time when the speed increased 3000 r/min, the propellant temperature at the outlet of the hydrogen peroxide pump would increase about 1 °C and that of the kerosene pump 5 °C. The experiment can promote the application of the electric pump with hydrogen peroxide and kerosene in rocket propulsion systems with pintle injectors to realize a large regulating ratio.