尾喷管内外超声速流场数值模拟

采用有限元法数值模拟带二次流可调收－扩喷管内外跨声速和超声速流场，在计算中采用四边形等参元确定位移函数，利用加权余量法中的Galerkin法建立有限元方程，数值研究三种型式喷管和四种飞行工况下尾喷管内外流场。计算结果与实验数据符合较好，说明可用此数值模拟技术帮助开展实验研究，进行尾喷管优化设计。

Numerical investigation of internal and external supersonic flows of nozzle

The definite element method was developed for simulating the transonic flowfields and supersonic exhaust flows of convergent divergent nozzles with the secondary flow. The shape and the secondary flow rate of the nozzles were adjustable. The 2 D 8 node and axisymmetric quadrilateral elements were used for shape functions. The Galerkin algorithm was employed in the solution of N S equation of the compressible viscous flow. Calculations under four different operating conditions were obtained with the present method. The comparison between predictions and experimental data shows that the numerical procedures are reliabe and can be used to assist the experimental study and predict the jet nozzle performance for the optimum design.