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采用数值分析方法分析了跨声速喷管无粘流动和超声速射流对挡流板的冲击流场。该方法是对激波流动添加了显式人工粘性项，控制方程仍为Ｎａｖｉｅｒ—Ｓｔｏｋｅｓ方程，采用ＭａｃＣｏｒｍａｃｋ二阶显式预报一校正差分格式求解。对于边界点采用的是参考平面特征线法，粘性项当作源项处理，并使用时间相关法在渐近解经过长时间后收敛至稳态解。对很不均匀的初始数值面进行了数值平滑，使计算加速收敛至稳态。通过计算际发动机的跨声速喷管流场，并以此作为射流计算的输入数据，分析了影响挡流板产生阻力的因素，计算了超声速射流对挡板的冲击流场，获得了阻力大小。结果表明，挡流板的迎风面积是决定阻力大小的主要因素。
Numerical simulation is used to analyze the impact flow of transonic nozzle with non-stick flow and supersonic jet on the baffle. The method adds an explicit artificial viscous term to the shock wave flow, and the governing equation is still Navier-Stokes equation, which is solved by MacCormack second-order explicit prediction and a modified difference scheme. For the boundary point, the reference plane characteristic method is adopted, and the viscous term is treated as the source term, and the time-dependent method converges to the steady-state solution after the asymptotic solution passes for a long time. Numerical smoothing of a very uneven initial numerical surface accelerates the calculation to a steady state. By calculating the intercostal flow field of the intercostal engine and using it as the input data for the jet calculation, the factors affecting the resistance of the baffle are analyzed. The impact flow of the supersonic jets on the baffle is calculated and the resistance is obtained. The results show that the baffle windward area is the main factor that determines the size of resistance.