Film cooling characteristics of cylindrical holes with ribbed crossow

Experimental measurements have been carried out to investigate the film cooling characteristics of cylindrical holes with coolant crossow in ribbed channel. The local film cooling Effectiveness and heat transfer coefficient were measured with transient liquid crystal technique over a series of crossow Reynolds number and blowing ratio. The results show that the ribbed channel crossow produces asymmetrical distributions for film cooling Effectiveness and heat transfer coefficient. The crossow can enhance the lateral spreading of film jets. Larger crossow Reynolds number produces higher film cooling Effectiveness, especially at high blowing ratios. Under the same crossow Reynolds number, the heat transfer coefficient increases as the blowing ratio increases, while the film cooling Effectiveness increases firstly and then decreases. Under conditions with small crossow Reynolds number and high blowing ratio, heat transfer is notably enhanced in the midspan region of adjacent holes and the region near hole exit.