攻角和端壁滑移对凹槽叶顶间隙流动传热的影响  

Effects of attack angle and endwall slippage on flow and heat transfer of blade squealer tip

作　　者：李广超[1] 张占东[1] 张魏[1] 寇志海[1] 

机构地区：[1]沈阳航空航天大学辽宁省航空推进系统先进测试技术重点实验室,辽宁沈阳110136

出　　处：《热力发电》2016年第2期40-46,共7页Thermal Power Generation

基　　金：国家自然科学基金项目(51306126;51406124)

摘　　要：以某燃气轮机高压涡轮动叶为研究对象,在主流雷诺数为9×104条件下,对进气攻角分别为-5°,0°,5°以及端壁有、无滑移时的凹槽叶顶旋涡结构和换热系数进行了数值模拟及实验验证。结果表明:压力系数模拟计算结果与实验数据吻合较好,说明本文数值模拟结果有效;无端壁滑移时,叶顶靠近压力面侧前缘产生的泄漏涡向吸力面和尾缘同时发展,叶顶换热系数沿叶型中弧线方向减小;端壁滑移缩小了泄漏涡尺度,泄漏流均匀地从压力面流向吸力面;叶顶换热系数沿垂直于弦长方向减小;端壁滑移虽然降低了间隙内泄漏流速度,但却使叶顶平均换热系数略有增大;端壁滑移使3种攻角的叶顶最高换热系数分别降低了7.5%,8.1%和19.2%;攻角从-5°变化到5°,端壁滑移和无滑移时的最高换热系数分别降低了14.9%和22.4%,无论端壁有无滑移,叶顶平均换热系数均降低了约11.8%。By taking the rotor blades of a high pressure gas turbine as the research object,the leakage vortices and heat transfer coefficients of the squealer tip were numerically simulated under conditions with Reynolds number of 9×104 and attack angle of-5,0°and 5°,to investigate the effects of attack angle and endwall slippage on the flow and heat transfer in the blade tip gap.Moreover,the simulation results were verified experimentally.The results show that,the calculated pressure coefficients are consistent with the experimental data,implying the numerical simulation results were valid.When the endwall are not slipping,the vortices induced by the leaking from the leading edge neighboring to the pressure side developed to both the suction side and the trailing edge.The heat transfer coefficients on the tip decreased along the camber curvature from the leading edge.The slippage of the endwall weakened the leakage vortices and the fluid of the leakage flowed uniformly from the pressure side to the suction side.The heat transfer coefficients on the tip decreased along the direction normal to the chord.The slippage of the endwall decreased the velocity magnitude of the leakage,but the averaged heat transfer coefficients increasd slightly.The maximum value of the heat transfer coefficients on the tip decreased by 7.5%,8.1%,and 19.2% by the slippage of the endwall with three attack angles,respectively.The maximum values of heat transfer coefficients on the tip both with and without the slippage decreased by 14.9% and 22.4%,respectively,and the averaged heat transfer coefficients both with and without the slippage decreased by 11.8% when the attack angles changed from-5°to 5°.

关 键 词：燃气轮机 涡轮叶片 凹槽叶顶 换热系数 间隙流动 进气攻角 端壁滑移 数值模拟 

分 类 号：TK47[动力工程及工程热物理—动力机械及工程]