跨声速高压涡轮静叶水滴喷雾/空气冷却性能研究

Research on Mist/Air Cooling Performance of Transonic High Pressure Turbine Stator

采用气热耦合的方法对径向对流内冷方式的Mark-Ⅱ跨声速高压涡轮静叶进行数值仿真准确度验证,分析湍流模型、转捩模型和有无耦合对计算结果准确度的影响。在此基础上,通过对该对流冷却通道的冷却空气加湿来研究加湿前后冷却性能强化。由于单纯的对流冷却时冷却空气流速快,液滴蒸发不充分导致两相流冷却效能未充分发挥,所以将Mark-Ⅱ改型为气膜+对流复合型冷却叶片,详细讨论不同加湿量和液滴直径对叶片强化换热的影响,同时给出加湿对于跨声速叶栅流场和边界层的影响。

Conjugate heat transfer methodology is used to verify the accuracy of numerical simulation program for the Mark II transonic high pressure turbine stator which is cooled internally by air flowing through radial round pipes,and different turbulence models and transition models is employed to analyze the influence on results.On the basis of it,through injecting mist into the convection cooling channel to discuss the improvement of cooling performance.The cooling air flow speed and inadequate droplet evaporation duo to simple convection cooling structure and two-phase flow cooling performance is not fully play.And then,a compound cooling blade with film cooling and convection cooling techniquesis acquired which is modified from the blade of Mark II,the effects of various parameters including mist concentration and water droplet diameter on the improvement of cooling performance are investigated,meanwhile the impact of mist cooling is presented for transonic cascade flow field and boundary layer.