In order to understand the cooling characteristics of the double-outlet film holes further

the platform for testing film cooling effectiveness was established.The cooling effectiveness of the cycle holes and four kinds of double-outlet holes with various orientation angles was studied at the blowing ratios from 0.3 to 2.0 by infrared measurement.The results show that:compared with the cycle hole

the surface averaged cooling effectiveness of the double-outlet holes is improved by 18%-37% with 30

45 and 60 degrees of orientation angles.At the low blowing ratios

the cooling effectiveness of the double-outlet holes with 30 degree of orientation angles is most significantly improved.At the high blowing ratios

the cooling effectiveness of double-outlet holes with 60 degree of orientation angles is most significantly improved.The double-outlet holes with 45 degree orientation angles can significantly improve the cooling effectiveness at both high and low blowing ratios.The cooling effectiveness of the double-outlet holes with 75 degree of orientation angles is lower than that of the cylindrical holes.