基于出口导流控制的超声速进气道性能研究

Investigation on the performance of a supersonic inlet with diversing flow control on the exit

针对进气道内型面存在较大弯段而导致的流动分离问题,提出了一种对进气道出口弯段进行导流控制的概念,设计了3种不同的导流格栅方案,采用数值仿真方法对不同导流格栅方案的超声速进气道流动进行了对比分析,获得了不同导流格栅对进气道流场结构和工作性能的影响特性.结果表明:利用格栅对进气道进行导流控制,可以改善进气道出口弯段的流场结构和压力分布,避免进气道出口发生流动分离.通过对格栅型面进行优化可以显著改善进气道的工作性能,采用类翼型导流格栅的进气道性能改善幅度最大,马赫数为3.5条件下,其稳定工作裕度和出口总压恢复系数分别提高10.3%和9.8%,冷流内阻降低5.3%.

Due to the flow separation induced by the severe curved shape of the inlet, a flow-control method based on the diversing flow grid was brought forward. Three different diversing flow grids were designed and a comparison of the supersonic inlet performance was conducted with a computational fluid dynamics method. Effects on the flow structure and working performance of the inlets with different diversing flow grids were attained. Results indicate that taking the grid as the flow control measure could avoid flow separation on the exit of the inlet by improving the flow structure and pressure distribution of the curved duct. It is proven that the performance of the inlet could be obviously improved by optimizing the diversing grid. Stability and total pressure recovery coefficient of the inlet with adoption of the airfoil shape grid could be raised by 10.3%and 9.8% at utmost while its interior resist- ance could be reduced by 5.3 % at Mach number of 3.5.