高负荷低压涡轮叶片边界层损失机理  

Boundary layer loss mechanisms of highly-loaded LP turbine blades

作　　者：綦蕾[1] 邹正平[1] 刘火星[1] 王雷[2] 

机构地区：[1]北京航空航天大学航空发动机气动热力国防科技重点实验室航空发动机数值仿真研究中心,北京100191 [2]中航工业沈阳发动机设计研究所涡轮室,沈阳110015

出　　处：《中国科技论文》2012年第11期830-835,共6页China Sciencepaper

基　　金：国家自然科学基金资助项目(51106004);高等学校博士学科点专项科研基金资助项目(20101102110011)

摘　　要：对不同雷诺数、不同来流湍流度条件下某典型高负荷低压涡轮叶片边界层流动进行了数值模拟,详细分析了雷诺数和湍流度对边界层分离与转捩的影响机制。结果表明:随着雷诺数的降低叶栅出口总压损失增大,一方面雷诺数减小吸力面边界层抗分离能力减弱,边界层分离引起损失增加,另一方面雷诺数减小吸力面层流边界层摩擦损失增大;随着湍流度的升高叶栅出口总压损失先减小后增大,这是因为低湍流度时流动分离损失占主要地位,湍流度增大分离减弱,叶栅总压损失减小;高湍流度时流动分离损失较小,边界层摩擦损失占主要地位,湍流度增大摩擦损失相应增加,叶栅总压损失增大。Numerical simulations of boundary layer flow of a highly-loaded low pressure turbine airfoil with different Reynolds numbers and freestream turbulence intensities（FSTIs） were carried out.The effects of Reynolds number and FSTI on the flow separation and transition were investigated.The results indicate that the total pressure loss at the cascade exit rises with a decrease of Reynolds number.The low Reynolds number causes the separation resisting ability of the boundary layer to diminish,and the flow separation loss to increase.Additionally,the friction loss of the laminar boundary layer increases as Reynolds number increases.The total pressure loss drops first and then rises with the increase in FSTI.This is because that the separation flow loss predominates at low FSTIs.The increased FSTI reduces the separation bubble size and,consequently,reduces the total pressure loss at the cascade exit.In contrast,at high FSTIs,the boundary layer friction loss predominates.The friction loss increases due to the increased FSTI,leading to the total pressure loss at the cascade exit.

关 键 词：分离 转捩 雷诺数 湍流度 高负荷低压涡轮 

分 类 号：V232.4[航空宇航科学与技术—航空宇航推进理论与工程]