液力透平偏工况下叶片表面流动分离特性研究  

Analysis of the Flow Separation Characteristics on Blade Surface of the Pump as Turbine at the Off-design Working Conditions

作　　者：林通 管嫦娥[1] 谢仁华[1] 朱祖超 Lin Tong;Guan Chang’e;Xie Renhua;Zhu ZuChao(School of Mechanical and Electronic Engineering,Jiangxi college of Applied Technology,Ganzhou,Jiangxi 341000,China;Key Laboratory of Ionic Rare Earth Resources and Environment,Ministry of Natural Resources,Ganzhou,Jiangxi 341000,China;National and Local Joint Laboratory of Fluid Transmission System Technology,Hangzhou,Zhejiang 310000,China)

机构地区：[1]江西应用技术职业学院机械与电子工程学院,江西赣州341000 [2]自然资源部离子型稀土资源与环境重点实验室,江西赣州341000 [3]流体传输系统技术国家地方联合实验室,浙江杭州310000

出　　处：《化工设备与管道》2023年第4期55-63,共9页Process Equipment & Piping

基　　金：江西省自然科学基金青年基金项目(20224BAB214056);江西省教育厅科学技术研究重点项目(GJJ214903);江西应用技术职业学院高层次人才科研启动项目(JXYYG2022002);国家自然科学基金(51906224,51906223,U2006221)。

摘　　要：由于离心泵反转作液力透平缺少活动导叶等导流装置,在偏工况下其性能会急剧下降,从而限制了透平的应用。转轮作为透平回收能量的核心部件,其内部流动特性的优劣会直接影响透平性能。为探究偏工况下叶片表面流动分离特性,文章首先通过数值计算方法预测了透平在不同工况下的水力性能,并进行试验验证了数值方法的准确性。随后,基于分离奇点理论及摩擦力线的拓扑分析方法诊断了叶片表面发生流动分离的区域,并建立了叶片表面流动分离与摩擦力线奇点类型之间的相互联系。最后,通过局部流动特征揭示了流动分离产生的原因。研究结果表明:不同工况下叶片表面流动分离的发生区域不完全一致,但从流动分离类型看来,当流动分离发生在吸力面时,分离类型主要为鞍点-螺旋分离点式分离、鞍点-分离结点式分离,而当流动分离发生在压力面时,分离类型主要为鞍点-分离结点式分离。叶片表面局部摩擦力线的奇点个数越多表示区域内流动越复杂,其中回流通常起始于附着线附近,而流动分离则发生分离线附近。研究结果可为液力透平的性能提升及运行调控提供参考。Due to the lack of flow guidance components such as guide vanes,the efficiency of the centrifugal pump as turbines(PATs)under the off-design operation conditions declines and limits its application.The impeller is the critical component of PATs energy recovery,and its inner flow characteristic determines the performance of PATs.In order to explore the characteristics of blade surface flow separation under off-normal working conditions,the hydraulic performance of the turbine under different working conditions was predicted by numerical calculation method,and the accuracy of the numerical method was verified by experiments.Then,based on the separation singularity theory and the topological analysis method of friction line,the flow separation area on the blade surface was diagnosed,and the relationship between the flow separation on the blade surface and the singularity type of friction line was established.Finally,the causes of flow separation were revealed through local flow characteristics.The results show that the regions of flow separation on the blade surface under different working conditions are not completely consistent.However,from the perspective of flow separation types,when flow separation occurs at the suction surface,the separation types are mainly saddle point-spiral separation and saddle point-junction separation,while when flow separation occurs at the pressure surface,the separation types are mainly saddle point-junction separation.The more singular point number of surface friction lines on the local blade surface indicated that the more complex the flow in this region.The backflow usually starts near the attachment line,while the flow separation occurs near the separation line.The research results can provide reference for the performance improvement and operation control of PATs.

关 键 词：液力透平 叶片表面 流动分离 数值模拟 偏工况运行 

分 类 号：TH311[机械工程—机械制造及自动化]