星用490 N发动机喷注器局部燃气泄漏试验

根据近期某卫星在轨故障模式,为了研究测压管嘴燃气泄漏对液体火箭发动机工作性能和温度特性的影响,以该卫星用第二代490 N发动机为试验对象,开展了测压管嘴在0.1、0.3、0.5 mm直径泄漏孔下的高空模拟热试车考核,对发动机真空推力、比冲和关键部位温度进行了测量。试验结果表明：试验条件下测压管嘴燃气泄漏对发动机工作稳定性没有影响;0.1 mm泄漏孔对发动机工作性能和各测点温度没有影响。随着泄漏孔直径增大至0.3 mm和0.5 mm,测压管嘴堵头烧蚀程度加深,发动机真空推力和比冲均值下降幅度分别仅为0.4%和1.4%,表明试验条件下测压管嘴泄漏对发动机工作性能的影响较小。燃烧室喉部温度试验结果不受泄漏的影响,喷注器测压管嘴及其附近、模拟卫星支架测点温度上升明显,氧化剂控制阀温度上升较小,远离测压管嘴的测点温度几乎不受高温燃气泄漏的影响。

Test on injector local gas leakage of 490 N engine for satellites

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 490 N engine for the satellite with the pressure measuring taps of leakage holes of 0.1, 0.3 mm and 0.5 mm 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 0.1 mm diameter had no effect on the engine performance and each temperature measuring point. As the leak hole diameter increased to 0.3 mm and 0.5 mm, 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.