Effect of hole space ratio on effusion cooling performance

Abstract EN

The film cooling effectiveness and local heat transfer coefficient for different hole space ratio have been experimentally investigated on a flat plate in the current study.

The investigations were done by using a single test transient IR thermography technique.

Three models of staggered holes arrangement are investigated.

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Each model is provided with five columns of holes, these models are arranged with staggered row holes.

The holes diameter is 4mm, the longitudinal distance (X/D) is 10, and the span distance between two neighboring holes (S/D) are 3, 5, and 7 respectively.

The attitude of the holes is fixed at inclination angle (θ = 30º ).

The blowing ratios, cold to hot air flow ratio, have been changed three times (BR= 0.5, 1.0, and 1.5) during the experimental program.

The experimental investigation showed that the thermal performance decreases as the space ratio (S/D) increases for all blowing ratios, and the film cooling effectiveness decreases as the blowing ratio increases for all the three models