自由流湍流度对某低压涡轮级气动影响的数值研究

Numerically investigate the effects of freestream turbulence on dynamics of a low-pressure turbine stage

基于Langtry-Menter转捩模型,定常求解雷诺平均的三维粘性N-S方程组,数值研究了不同雷诺数工况下,自由流湍流度(FST)变化对某低压涡轮级流场及性能的影响,揭示了FST对该低压涡轮级叶片吸力面表面流动及涡轮级效率雷诺数效应的影响规律;并基于一种损失分离方法,细分了FST对该低压涡轮级内部各损失分量,如叶型损失、端壁边界层损失,叶尖泄漏损失的影响.

Based on SST turbulence model coupled with Langtry-Menter transition model, a three-dimensional, vicous, steady CFD analysis was performed for investigating the effects of freestream turbulence on the dynamics of a LP turbine stage at different Reynolds numbers. From the CFD prediction results, the rules of freestream turbulence effects on the flow mechanics on blade suction surface, and on Reynolds number effects on this LP turbine stage efficiency were obtained. Also, based on a kind of loss separation method, freesteam turbulence effects on the flow loss components, such as the profile loss, the endwall boundary loss, and the tip clearance loss inside this LP turbine stage were further distinguished.