Conjugate Heat Transfer Predictions on Combined Impingement and Film Cooling of a Blade Leading Edge Model

In this paper, numerical simulation is performed to predict combined impingement and film cooling on a model of the turbine blade leading edge by the heat flow coupling method. The first-stage rotor blade leading edge of the GE-E³ engine high-pressure turbine is adopted for the simulation. The relative performances of turbulence models are compared with experimental data and the results show that standard k-ω model is the best, based on simulation accuracy. The standard k-ω model is adopted for the simulation. A grid independence study is also carried out. Five different mass flow ratios and seven different film cooling hole configurations are studied in detail. The results indicate that (1) the overall film cooling effectiveness on the leading edge surface and the Nusselt number on the target surface increase with increases of coolant mass flow ratio; (2) the blade leading edge temperature decreases with an increase in mass flow ratio; and (3) the area-averaged overall film cooling effectiveness increases with a decrease in spanwise film cooling injection angle, when the injection angle is lower than 25°, while it does not change much otherwise.