涡轮静叶栅二次流的数值模拟  

A Study of the Numerical Simulation of Secondary Flows in Turbine Stator Cascades

作　　者：李军[1] 苏明[1] 

机构地区：[1]上海交通大学动力机械与工程教育部重点实验室,上海200030

出　　处：《热能动力工程》2008年第1期16-20,共5页Journal of Engineering for Thermal Energy and Power

摘　　要：采用CFD软件Fluent数值求解了大转折角涡轮静叶栅三维流动,分析了叶栅沿流向各截面二次流及叶栅的气动特性,并研究了叶高以及入口攻角变化对叶栅二次流的影响。计算发现,由叶栅压力面向吸力面运动的二次流强度沿流向逐渐增大,引起吸力面附近端壁附面层不断壮大且在后部卷起,并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。通过不同叶栅工况的比较,发现叶高的减小以及攻角的增大会极大提高叶栅的二次流损失,其本质原因都是叶栅通道内二次流所占区域的扩大所致。By adopting CFD(computational fluid dynamics)Software Fluent a numerical solution for the three-dimensional flows in turbine stator cascades featuring a big turning angle has been achieved.The secondary flows along the flow direction on various sections of the cascade and its aerodynamic characteristics were analyzed along with an investigation of the influence of any change in blade height and inlet incidence on cascade secondary flows.It has been found from the calculation results that the intensity of the secondary flows,which move from the cascade pressure surface to the suction one,increases gradually along the flow direction,giving rise to the continuous consolidation of the boundary layer on endwall near the suction surface and also a curling-up at the rear portion.Moreover,the foregoing also has led to a drastic change of the total pressure loss coefficient and the outlet flow angle along the blade height.A comparison of the various cascade operating conditions shows that a decrease of blade height and an increase of incidence will drastically increase the cascade secondary-flow losses,the intrinsic cause of which invariably lies in the expansion of the area occupied by the secondary flows in the cascade passage.

关 键 词：二次流 涡轮 静叶栅 数值模拟 

分 类 号：TK402[动力工程及工程热物理—动力机械及工程]