Combined-Hole Film Cooling Designs Based on the Construction of Antikidney Vortex Structure: A Review

Film cooling is one of the most efficient and widely used cooling methods for high-Temperature components. The interaction between the film cooling jet and main flow creates the counter-rotating vortex pair (CRVP), which enhances the mixing between coolant and hot stream and lifts the coolant film off the protected surface. The desire to overcome the unfavorable effects of CRVP and thus efficiently improve cooling effectiveness promotes various new combined-hole designs for film cooling. In this review paper, a summary of previous progress on film cooling and a special focus on recent literature related to the combined-hole film cooling designs with less difficulty in machining are provided. The underlying mechanisms of the enhancement in cooling effectiveness and film coverage due to antikidney vortex structure by combined holes are analyzed. Some perspectives on future prospects are finally addressed.