基于非协调单元的液体火箭发动机推力室热结构分析

用巴兹公式和发动机的热力计算数据,得到了推力室内的燃气壁面对流传热系数和燃气温度的分布,并用有限单元法计算了推力室的温度场.在温度场计算基础上,采用Wilson非协调单元,对推力室的应力场进行了计算,其中位移函数采用二阶形式,将计算精度提高到二阶.结果表明:相比常规单元,Wilson非协调单元在计算结构比较复杂,温度梯度比较大的结构时,精度比较高,结果合理. 

Thermal structure analysis of liquid rocket engine thrust chamber based on non-coordinated element

Heat exchange coefficient of gas in thrust chamber and distribution of gas temperature were obtained from Baz formula with data of thermal calculation,and the temperature of thrust chamber was calculated by finite element method.Based on calculation of temperature,the stress of thrust chamber was carried out by Wilson non-coordinated element,in which displacement function was quadratic form.The result shows that,compared with typical element,using Wilson non-coordinated element can get higher calculation precision and more reasonable result in the analysis of high temperature gradient and complex thermal structure of thrust chamber.