摘要
应用数值方法对某型向心涡轮的可调导叶间隙流动结构及其涡轮性能的影响作了分析,间隙尺寸分别为1%、2%、4%叶高。计算结果表明:间隙加大,涡轮效率下降,流量增加,间隙流动所造成的流动损失是结构阻力型的。间隙对涡轮性能的影响主要来自于叶轮进口气流冲角的增加与叶轮反动度的提高。简单地修正导向叶栅的流动效率,不能反映间隙对涡轮整体性能的影响。
The aim of this paper is to present a numerical analysis of the tip clearance flow structure to evaluate its influence on the turbine＇s aerodynamic performances. Tip gaps are defined with respectively 1 %, 2%,4% of blade height. The results show that turbine efficiency＇s decrease and flow rate＇s increase are varying with gap size. Dynamic losses from tip leakage flow are characterized as those in resistant flow structures. Effects of tip gap on turbine performance are mainly originated from the increase of impeller＇ s incidence and turbine reaction. Simple modification of the stator＇s flow loss prediction can not represent the gap＇s effect on turbine overall performances.
出处
《热力透平》
2009年第4期244-247,251,共5页
Thermal Turbine
基金
上海市重点学科建设项目(J50501)
国防科技重点实验室研究基金项目(9140C3302030901)
关键词
向心涡轮
可调导叶
间隙流动
radial inflow turbine
variable guide blade
tip clearance flow
