低压涡轮叶型边界层相互作用的数值模拟

Numerical simulation for interaction between wake and boundary layer on a low-pressure turbine profile

关键词:  低压涡轮  非定常流  尾流  转捩模型+  数值仿真

Key words:  Low-pressure turbine  Unsteady flow  Wake  Transition model+  Numerical simulation

摘要:

基于Lantry-Menter转捩模型,应用商用流体计算软件求解非定常雷诺平均N-S方程组,对进口雷诺数为2.5×104,来流湍流度为2.5%,尾迹折合频率为0.92状态下的尾迹/PAK-B叶型边界层的相互作用进行了数值模拟。数值计算揭示的尾迹在叶栅通道中的输运特性、尾迹诱导卷起涡形成、尾迹诱导边界层转捩等物理机制大致符合相关实验定性描述。

Abstract:

The engineering design of high-lift or ultra-high-lift low-pressure turbines based on unsteady flow environments requires supports of proper numerical tools.Based on Langtry-Menter transition model,the interaction between wake and boundary layer on PAK-B profile was simulated by using commercial CFD code to solve the URANS equations,with inlet Reynolds number,free stream turbulence lever and the wake reduced frequency to be 2.5×104,2.5%,and 0.92,respectively.The physical mechanics disclosed by predicted results such as the transportation of wake,the development of roll up vortexes,and the transition induced by wake,showed a qualitative agreement with the open experimental descriptions.Additionally,the predicted results need further quantitative validation.