In order to get the effect law on the efficiency of gas film entrance structure and provide a reference for engineering application

3D discrete holes supersonic gaseous film cooling numerical simulations with different holes structure were investigated. Results showed that the film inlet structure affected the film cooling efficiency obviously. Flow coefficient affected the cooling directly so that film cooling effectiveness reduced 005 while flow coefficient decreased 013 for the axisymmetric entrance under calculation conditions. Meanwhile

lowing jet holes area change rate enhanced the cooling effectiveness

because the flow field with too fast area change rate can't develop fully

and the gaseous film flowed to both sides while the center was exposed to combustion gas. Design of a rectifying section in discrete holes exit will help to concentrate the coolant and keep off the cooling deterioration with the layer of film penetrated.