Abstract: In order to study the heat transfer characteristics of turbine blades, this article presents an experimental study of composite cooling of impingement and film on the leading edge of a turbine blade. The effect of factors on cooling effectiveness, such as blowing ratio, position of leading edge, main flow Reynolds number and comparison of temperature T_g/T_c, is investigated in detail. The experimental results show that cooling effectiveness improves with the increase of blowing ratio and deteriorates with the increase of T_g/T_c. Under the conditions used in this article, the optimal blowing ratio is about 1.0. The closer the cooling is to the stagnant point, the higher is its effectiveness. The Reynolds number of the main flow has a relatively small effect on cooling effectiveness, but the cooling effectiveness still increases with increasing Reynolds number as a whole.

Key words: turbine blade, composite cooling, experiment, cooling effectiveness, blowing ratio