气膜孔孔径变化对涡轮叶片全表面冷却特性影响研究

In view of the problem that the film hole diameters are different from their design values caused by laser drilling and coating spraying during the manufacturing，the effects of film hole diameter change on the cooling effectiveness in different regions of the blade were analyzed for a rotating turbine blade. According to the statistics from a real engine，the diameter of the film hole was larger after laser processing but smaller after coating spraying relative to the design value. Based on this，different models were established and conjugate heat transfer simulations were carried out. The results showed that the change of film hole diameter had a more significant effect on the cooling effectiveness in the region with strong external heat transfer boundaries. The comprehensive cooling efficiency near the trailing edge region was the best when the film hole diameter reached the design value，and the efficiency was positively correlated with the film hole diameter in the other positions. The increase of the film hole diameter significantly improved the comprehensive cooling efficiency by 164.13%/mm， which was far more than 78.72%/mm when the film hole diameter decreased. The change of film hole diameter had a great influence on the cooling efficiency of the leading edge， and the average influence degree can be up to 254.62%/mm，which need to be paid more attention in the design.