Film cooling performance of a fully cooled vane at high subsonic conditions

This work focuses on the experimental study of the heat transfer and film cooling characteristics of a fully cooled vane under high subsonic conditions; the transient heat transfer measurements with thermocouples were employed. The inlet Reynolds numbers of the cascade ranged from 3.0 × 105 to 9.0 × 105 and the exit Mach number was 0.8. Two freestream turbulence intensities (1.3% and 14.7%) and three mass flow ratios (5.5%, 8.4%, and 12.5%) were tested. The averaged film cooling effectiveness of the current vane with shaped holes was found to be increased by 15%–43% more than that of the vane only with cylindrical holes, and elevated turbulence intensity reduced the averaged film cooling effectiveness by3%–26%. The heat transfer augmentation of the current vane was lower than that of the vane only with cylindrical holes. With the mass flow ratio increasing, the heat transfer augmentation gradually increased on the pressure side, whereas it was nearly kept invariable on the suction side. The net heat flux reduction results showed that the vane with shaped holes significantly improved the cooling performance, whereas elevated turbulence intensity significantly deteriorated the cooling performance.