采用运动圆柱模拟动叶的涡轮静叶栅二次流研究(英文)  

Study on the Turbine Stator Secondary Flow Using Moving Cylinders to Simulate Rotating Blades

作　　者：李军[1] 苏明[1] 

机构地区：[1]动力机械与工程教育部重点实验室(上海交通大学),上海市闵行区200240

出　　处：《中国电机工程学报》2009年第26期92-100,共9页Proceedings of the CSEE

摘　　要：采用CFD软件Fluent数值求解大转折角涡轮静叶栅的三维流动,详细分析叶栅沿流向各截面的二次流发展及叶栅气动特性,并进行网格无关性论证。研究发现,叶栅通道内逐渐增大的横向压力梯度引起沿流向叶栅总压损失的增大和出口角的波动。高损失区首先在近壁区产生,随着流动向下游发展,高损失区沿叶高方向扩大,引起吸力面附近端壁附面层不断壮大且在后部卷起,导致沿叶高总压损失系数和沿叶高出口气流角的剧烈变化。随后发现叶高的减小及攻角的增大会极大提高叶栅的二次流损失。采用位于静叶栅前后的运动圆柱列替代静叶栅上下游动叶。发现圆柱尾迹进入叶栅流道的位置不同,对叶栅总压损失有较大影响。叶栅后圆柱列的位置不同也对静叶斜切口的流动特性产生影响。对涡轮内部流场的研究和优化提供有益的参考。Computational fluid dynamics method （CFD） was used to solve the three-dimensional flowfield of one-stage turbine stator cascade with a large turn angle. The stator＇s pneumatic characteristics and the secondary flow were analyzed in detail. Moreover, grid independence was considered during the simulation. As a result, the secondary flow from the pressure surface to the suction surface enhances gradually along with the flow direction, which causes the head loss and the outlet angle to fluctuate. Firstly, high head loss arises at the region near the endwall and stator surfaces, the reason is that the transverse pressure gradations in flowfleld strengthen and the secondary flow region expands in this instance. At the same time, the strength of the secondary flow increases when the stator height decreases or the inlet attack increases. In particular, moving cylinders replace the rotating blades which are situated at upstream and downstream of the studied stators. The head loss varies greatly when the inlet cylinder wake is situated at different positions. Also, the cylinder rows downstream have the apparent effect on the oblique zone of the stators. It provides an important reference for the optimization and study on the inner flowfield of turbomachinery.

关 键 词：二次流 涡轮 静叶栅 数值模拟 圆柱 总压损失 

分 类 号：TM311[电气工程—电机]