马赫数3～6宽速域内转进气道优化设计

基于对轴对称基准流场参数化研究选取半径适当小的可变中心体，再对其他设计参数进行灵敏度分析，得到设计参数对基准流场整体性能的影响规律，系数c的影响最为明显，同时各个设计参数之间耦合效应影响也很大。运用样本数据库，构建相应的神经网络近似模型并结合邻域培植多目标遗传算法对轴对称基准流场在马赫数为6时进行三目标优化，优化后的基准流场内收缩比降低了7.7%，总压恢复系数提高了2.3%，并且静压比提高了7.1%。基于此优化结果，进行内转进气道型面设计并对其在马赫数为3～6条件下黏性数值模拟，结果表明:优化后的内转进气道在马赫数为3工作时能够正常起动，在马赫数为4～6工作时，进气道有较高的压缩量，较好的流量捕获能力和总压恢复性能。 

Optimization design of the inward turning inlet in the Mach number 3-6 wide velocity domain

Based on the parameterization study of the axisymmetric basic flowfield, a variable center body with properly small radius was selected, then the sensitivity analysis of other design parameters was conducted to obtain the influence law of design parameters on the overall performance of the basic flowfield. This showed that the coefficient c had the most obvious effect, and the coupling effect between various design parameters was also significant. The sample database was used to construct the corresponding neural network approximate model, and the three-objective optimization of the axisymmetric basic flowfield at Mach number of 6 was carried out in combination with the neighborhood cultivation multi-objective genetic algorithm. After the optimization, the internal compression ratio in the basic flowfield reduced by 17.7%, the total pressure recovery coefficient increased by 2.3%, and the static pressure ratio increased by 7.1%. Based on the optimization results, the inward turning inlet profile was designed. The results from its viscous numerical simulation at Mach number of 3-6 show that the optimized inward turning inlet can start normally at Mach number of 3, and has higher compression, better flow capture ability and total pressure recovery performance at Mach number of 4-6.