LAUSR

Abstract Experimental tests are performed in the current study to explore the overall cooling performance of a combined slot injection/effusion array cooling structure. The pure slot injection and pure effusion array cooling schemes are taken into consideration for the comparison purpose. In addition, numerical simulations on the adiabatic and overall cooling effectiveness are also performed to illustrate the conjugated effects, such as internal convective heat transfer inside the coolant flow channel, thermal conduction inside the perforated plate, and internal cooling in the multiple holes, on the film cooling performance. The combined cooling scheme overcomes respective drawback of slot injection cooling in its decayed stage and effusion array cooling in its developing stage, thus producing a more ideal cooling performance over the entire protected surface under the same coolant usage. Due to the conjugated effects, the influence of adding slot injection on improving overall cooling effectiveness is significantly weaker than that on the adiabatic cooling effectiveness. Related to the pure slot injection or effusion array cooling scheme, the benefit of combined cooling scheme on the film cooling improvement is dependent on the blowing ratio. Under a combination of Msl = 0.5 and Meff = 0.4, it produces more obvious improvement on overall cooling effectiveness. While under a combination of Msl = 0.5 and Meff = 1.2, the overall cooling effectiveness in the front zone of effusion array is a little less than the pure injection scheme.