叶片顶端跨音速叶型的气动性能分析与优化  

Flow Analysis and Profile Optimization of Transonic Blade Tip Section

作　　者：刘颖超 陈榴[1] 戴韧[1] 杨其国 LIU Yingchao;CHEN Liu;DAI Ren;YANG Qiguo(School of Energy and Power Engineering,University of Shanghai for Science and Technology,Shanghai 200093,China)

机构地区：[1]上海理工大学能源与动力工程学院,上海200093

出　　处：《动力工程学报》2021年第10期842-848,858,共8页Journal of Chinese Society of Power Engineering

基　　金：国家科技重大专项资助项目(2017-V-0016-0069)。

摘　　要：应用流动计算分析软件CFX,对某大型汽轮机末级动叶顶部截面叶型的跨音速流动进行了数值模拟研究,分析叶栅中激波结构特征和流动损失机理。采用3阶Bezier曲线表达叶型中弧线,2阶与3阶Bezier曲线组合表达叶型厚度分布,结合Kriging代理模型优化叶型,改善气动性能。结果表明:末级动叶顶部截面叶型气动损失主要与激波强度及其反射位置有关;叶型优化后,叶栅内激波强度减弱,相比原叶型,激波损失减少约32%,同时削弱了激波对边界层的影响,边界层损失降低约17%;优化叶型总压损失下降24%,气动性能明显提高。The flow analysis software CFX was used to simulate the transonic flow in the last stage blade tip section of a steam turbine, and the shock wave characteristics and flow loss mechanism in the cascade were analyzed. The third-order Bezier curve was adopted to shape the camber line of the blade profile. A combination of the second-order and third-order Bezier curves was used to prescribe the thickness distribution along the blade chord. Kriging surrogate model was combined to optimize the blade profile and improve the aerodynamic performance. Results show that the aerodynamic loss of the tip section of last stage rotor blade is mainly related to the shock intensity and its reflection position. After the blade profile is optimized, shock intensity in the cascade is weakened, and shock loss is reduced by about 32% compared to the original blade profile. At the same time, the impact of the shock wave on the boundary layer is weakened, and the boundary layer loss is reduced by about 17%. The total pressure loss of the optimized blade profile is reduced by 24%, and the aerodynamic performance is significantly improved.

关 键 词：跨音速叶栅 激波强度 气动损失 优化设计 

分 类 号：TK263.3[动力工程及工程热物理—动力机械及工程]