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.