基于发动机高模试车的高温隔热屏热模型修正技术

Modification of High Temperature Heat Shield Thermal Analysis Model Based on Altitude Simulated Test

与常压环境地面试车相比,发动机高空模拟试车的热源分布更接近于实际飞行工况,本文通过搭载高模试车验证了高温隔热屏设计的正确性。通过考虑高温隔热屏层间气体导热和接触导热等,对高温隔热屏的传热模型进行了修正,其计算结果与高空模拟试车搭载试验结果的误差较小。在考虑真空引射背景红外辐射以及真空舱内气体与发动机及隔热屏的导热后,利用修订的高温隔热屏的当量热导率,进行了上面级高空模拟整机热分析,进一步提升了热模型的分析精度。

The heat source distribution of engine in altitude simulated test is relatively similar to real flight case compared to the normal pressure test case. In this article,the correctness of high temperature heat shield design is validated through altitude simulated test. The heat transfer model is modified by considering the gas conduction and contact conduction between each layer in high temperature heat shield. This thermal model has a relative high precision to the data getting from the altitude simulated test. Thermal model of the main engine and high temperature heat shield in altitude simulated test is made. Then,it is modified by considering the infrared radiation and the heat conduction with the gas in vacuum chamber.