Convective Heat Transfer in a Triple-Cavity Structure Near Turbine Blade Trailing Edge

The present study explores the internal heat transfer in a triple-cavity cooling structure with a ribbed lip for a turbine blade trailing edge. The design consists of two impingement cavities, two sets of crossover holes, a third cavity and an exit slot with eleven ribs attached to it. Local heat transfer in each subregion is determined. Results indicate that the highest heat transfer occurs in the second impingement cavity. The exit slot area between the ribs is identified as a region of low heat transfer in the overall design. A comparison with enhancement induced by arrays of pin fins and fins of other geometries reveals that the triple-cavity design represents a lesser quality cooling scheme in the range of Reynolds numbers tested. Further improvement of the convective heat transfer at the exit slot with either film cooling, or different rib geometries appears to be essential to make the triple-cavity strategy superior to those of the traditional approaches for cooling of blade trailing edge.