三维设计思想在子午流道大扩张角条件下的应用

根据三维设计思想,提出了针对子午流道大扩张角条件下涡轮导向叶栅的设计思想.研究结果表明:在子午流道的设计上,采用减小内端壁扩张角及加大外端壁扩张角的方式,可有效保证内端壁附近气流的抗分离能力,并且导向叶片采用正倾斜设计,以降低通道涡的径向迁移,从而减小或消除导叶尖部气流的分离,增加尖部附近气流的抗分离能力,达到减少损失的目的.该方法现已在某航空发动机高性能低压涡轮气动设计中进行了成功的应用和验证. 

Application of wide angle diffused meridian passage with three-dimensional design concept

Based on the three-dimensional design concept, a design method of low pressure turbine nozzle blade in wide angle diffused meridian passage was presented. The result indicates that smaller inner wall angle of divergence and bigger outer wall angle of divergence should be used to keep the flow stability near inner wall when design meridian passage, meanwhile make the vane lean to pressure side to increase the reaction near inner wall and keep the lean direction near outer wall to decrease the trend of passage vortex moving to mean radius for decreasing or eliminating the possibility of flow separation and increasing flow stability near the outer wall, and so decreasing the loss. This method has been applied and verified on a real aero-engine low pressure turbine.