The film cooling effectiveness of the tangential discrete holes film cooling configuration with different hole diameters and arrangement was experimentally investigated using infrared camera.The empirical correlations of cooling effectiveness to blowing ratio and non-dimensional flow-wise distance(X/S) were obtained

which agreed well with the experimental results.The results show that

for the present investigation conditions

the film cooling effectiveness will be increased with the increase of blowing ratios and the diameter of film hole;with the same blowing ratios and porosity of holes

the hole arrangement has little effect on cooling effectiveness.