关键词: 涡轮叶片;薄膜冷却;传热系数;实验

Abstract: A semicylinder nose is used in test models to simulate a turbine blade leading edge with film cooling.Four models with ejection holes at different angles and positions for film cooling are used in this paper.The external heat transfer coefficient distributions along the leading edge region with and without film cooling are measured separately.It is observed from the experiments that the main-stream boundary layer is damaged due to the existance of film jets, resulting in an enhancement of external heat transfer coefficients,especially in the vicinity of film holes.The effect of film cooling on external heat transfer coefficients increases with the blowing ratios of film jets.Four sets of empirical correlations of the enhancement of the external heat transfer coefficients showing their variations with the main stream Reynolds no,, ReD, blowing ratios, M, and nondimensional distances, x/d, are presented in this paper.

Key words: Turbine blade;Film cooling;Heat transfer coefficient;Test