International Scientific Journal

Thermal Science - Online First

online first only

Impact of V-shaped interrupted ribs in cross-flow channels on film cooling

This study primarily investigates the enhanced heat transfer of V-shaped ribs within an internal crossflow channel and their impact on external film cooling performance. The aim is to assess the advantages of V-shaped ribs in the cooling of gas turbine blades. The research specifically discusses the internal heat transfer efficiency of smooth channels, channels with V-shaped ribs, and channels with intermittently placed V-shaped ribs at a blowing ratio (M) of 0.5 and three different Reynolds numbers. The results indicate that the vortices generated by the coolant passing through the positive V-shaped ribs and intermittently placed V-shaped ribs effectively impinge on the upper and lower surfaces, thereby enhancing heat transfer performance. Regarding film cooling, under low Reynolds number conditions, the film cooling efficiency of the positive V-shaped ribs is 9% to 20% higher than that of the smooth channel. Under high Reynolds number conditions, the film cooling efficiency of the negative V-shaped ribs significantly increases, reaching 29% to 120%. The study demonstrates that rib shape and inlet Reynolds number have a significant impact on the swirl intensity of the coolant in the film cooling holes, and fluid with a certain swirl intensity exhibits better film cooling efficiency.
PAPER REVISED: 2024-04-04
PAPER ACCEPTED: 2024-04-07
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