星用490N发动机喷注器局部燃气泄漏试验

In order to study the effect of the injector pressure measuring tap gas leakage on the working performance and temperature characteristics of the liquid rocket engine according to the recent failure mode of a certain satellite in orbit, the second-generation 490N engine for the satellite with the pressure measuring taps of leakage holes of 0.1, 0.3mm and 0.5mm diameters respectively was used to carry out the high-altitude simulation hot fire tests for the first time in China. The engine vacuum thrust, vacuum specific impulse and important temperature points were measured. The test results showed that the gas leakage of the pressure measuring tap had no effect on the engine working stability under the test conditions. The leak hole of 0.1mm diameter had no effect on the engine performance and each temperature measuring point. As the leak hole diameter increased to 0.3mm and 0.5mm, the ablation of the pressure measuring taps was deepened, and the average vacuum thrust and vacuum specific impulse of the engine decreased by only 0.4% and 1.4%, respectively, indicating that the gas leakage of the pressure measuring tap had little effect on the engine working performance under the test conditions. The throat temperatures of the combustion chamber were not affected by gas leakage. The temperatures of the pressure measuring tap and its vicinity on the injector and the simulated satellite bracket rose significantly, and the oxidizer control valve temperature rose insignificantly. The temperatures of the measuring point away from the pressure measuring tap were not affected by the leakage of high-temperature gas.