高压涡轮冷却叶片叶顶结构气动与传热

开展了叶顶结构及间隙变化对高压涡轮冷却叶片气动与传热性能影响的研究,建立了四种不同叶顶结构的涡轮冷却叶片几何与数值分析模型,进行了高精度流热固耦合分析,得到了不同叶顶结构及间隙对涡轮冷却叶片气动与传热性能影响的数值分析结果。结果表明:不带射流孔叶片随着叶顶间隙的增大,总压损失增加;由于近壁面处存在的涡流,凹槽叶顶结构能够减少叶顶燃气泄漏,阻碍叶顶平面高温燃气的流动与热交换;叶顶射流孔冷却效果明显,能够大幅度降低叶顶平面温度。在相同叶顶间隙下,凹槽射流叶片具有最高的气动性能。

Aerodynamic and Heat Transfer of Cooling Blade Tips for High Pressure Turbine

The aerodynamic and heat transfer performance of high pressure cooling turbine blade tips were studied.Four blade geometry and simulation models with different tip features and tip clearances are discussed.Coupling aerodynamic and heat transfer method is used to accomplish the simulation.The results show that total pressure loss of blade tip without injection holes increases with the tip clearance.Recessed tip can greatly reduce the heat transfer between tip surface and high temperature gas,and also it reduces tip leakage,to some extent.That is because it exists obviously eddy near the tip surface.Tip injection holes can cool the tip surface effectively,and it will greatly reduce the temperature of tip surface.Recessed tip blade with injection holes performance least leakage under the same tip clearance.