Abstract
Impingement cooling is an extremely effective heat transfer enhancement technique. Though its feature is that heat transfer coefficient is a maximum at the stagnation point and decreases with distance along the plate. This paper shows the result of experimental and numerical study about impingement cooling for promoting heat transfer coefficient on the wall jet region by ribs as a part of enhancing cooling efficiency inside the turbine vanes. The effect of the rib height, the rib location, and the pitch of two ribs are investigated. The heat transfer measurements were performed using the naphthalene sublimation method. The AKN model was found to predict reattachment length correctly, which then resulted in good agreement of the local heat transfer coefficient distributions between experiments and numerical simulations except the stagnation region.
