单组元发动机推力室在轨温度数值仿真

Numerical simulation for temperature in a monopropellant thrust chamber on the orbit

建立了单组元发动机推力室系统(包括结构部件如隔热框、催化床、喷管等)的传热模型。在此基础上,应用有限元数值计算的方法,将模型进行轴对称Delaunay非结构化网格剖分,并完成瞬态温度场的模拟计算,进行推力室在轨温度的数值仿真。结合计算结果分析了热回浸现象、催化床电加热效能以及外空间辐射换热等问题。最后指出,隔热框的防热设计和空间辐射散热有效地隔绝了热回浸对电磁阀和喷注器的不良影响,并论证了催化床的电热丝加热是保证催化床在工作前维持一定温度范围之内的可靠方法。

Based on a thermal model of monopropellant thrust chamber system including its components such as adiabatic frame, catalyst bed, nozzle etc., temperature simulation was carried out by FEM with axisymmetric unstructured Delaunay girds generation and transient temperature distribution. Thermo-soakback phenomena, electrical heating efficiency of catalyst bed and outer space radiation were analyzed. The results show that the insulation design of adiabatic frame and outer space radiation on nozzle can prevent blight of thermo-soakback on electromagnetic brake and jet generator. It also shows that electrical heating is a reliable method which ensures that a permissive temperature range can be maintained before work.