引射喷管的气动性能和传热计算

对某型飞机引射喷管装三种机尾罩时的推力性能和机尾罩温度进行了计算，主流和次流的特性分别用特征线法和一维方法计算，为了计算机尾罩的温度，建立了一种简化的一维模型，计算结果与试飞实测数据吻合良好，引射喷管装三种机尾罩的比较表明：切短的机尾罩可以在推力下降不太多的同时改善机尾罩温度。

CALCULATION OF AERODYNAMIC PERFORMANCE AND HEAT TRANSFER OF AN EJECTOR NOZZLE

The thrust performance and the shroud temperature distribution of three shrouds of an ejector nozzle was calculated. In order to obtain the performance, the characteristic method is used to calculate the primary flow field; the one dimensional method is used to calculate the secondary flow. The viscous mixing effect between the two streams is considered by the constant pressure jet theory. As for the heat transfer, a simplified one dimensional model is presented to consider the heat balance of each layer from the afterburner to the shroud. Under the condition of the known inner wall temperature, a heat balance differential equation was established. Then it was integrated to get the temperature distribution of the shroud. Results show a fine agreement with the record of fight test. Comparison of three shrouds of an ejector shows that, a cutted shroud is able to be used to improve the shroud temperature, meanwhile the thrust will not be decreased too much.