阶梯型发射管内燃气流场的正格式数值模拟

为研究阶梯型发射管内燃气流场特性,将2维守恒方程的正格式方法发展到轴对称Euler方程组的求解,并对阶梯型发射管内燃气流场进行了数值计算,给出了发射管内流场的流动图形及发射管中心线和管壁的压力分布,分析了管内复杂波系结构的变化趋势.验证算例结果与实验照片反映的流动特征及已有数值格式的计算结果吻合较好,表明推广是有效的.该方法能够较好地捕捉到包括射流边界、相交激波、马赫盘、三波点和二次流等阶梯型发射管内流场波系结构,计算结果在发射管轴线反射点附近的分辨率较高;数值解具有较大的梯度变化,表明该方法对激波具有较强的捕捉能力.

Numerical Simulation of Flow-Field of Gas in Stepped Launcher Tube by Positive Scheme

To study the flow-field characteristics of gas in Stepped Rocket Launcher Tube(SRLT),the second-order positive scheme was developed to solve the axisymmetric Euler equations based on the two-dimensional conservation laws,and the flow-field of gas in SRLT was simulated numerically.The flow figure of flow-field in SRLT,pressure distribution on the center line and tube wall of SRLT,were given.The variation trend of structure of complex wave in SRLT was analyzed.The example results agree well with experimental data and other numerical scheme,which shows the effectiveness of the development.By the method,the wave structures of flow-field in SRLT can be captured including jet boundary,intersection shock wave,Mach disk,the triple point and the secondary flow,etc.The method shows high resolution at discontinuous point along the axis of launcher tube,and the numerical solution has steep gradient.The method has high capability in capturing shocks.