Abstract: The numerical calculation was carried out to contour design of low pressure turbine which has great diffused angle casing. Seven schemes were bought forward and testified by 3D N-S solver. The results show that the change of shroud of diffused meridional passage have great effect on energy loss at exit of low pressure guide vane. The excellent aerodynamic performance design of shroud of diffused meridional passage can weaken flow separation which caused by great diffused angle and reduce the loss.

Key words: Aircraft engine;Turbine cascade;Cascade flow;Numerical calculation;Wall line;Contour design

摘要： 采用数值计算方法对具有大扩张角中间机匣的某型涡轮低压级子午流道型线进行了改型设计 ,提出了7种型线设计方案 ,并应用N S方程全三维粘性求解程序对 7种方案进行了验算。结果表明 :子午扩张型流道外壁型线的改变 ,对低压导向器出口能量损失的影响是显著的 ,设计气动性能优良的子午扩张型线能明显削弱由于大扩张角引起的气流分离 ,降低涡轮低压级的损失。

关键词: 航空发动机;涡轮叶栅;叶栅流;数值计算;壁面线;改型设计