The effect of blade platform contour shape on leakage flow film cooling effectiveness was experimentally investigated on two commonly used axisymmetric profiles — the dolphin nose and the shark nose. Engine operating conditions were simulated in a scaled warm cascade, which was built based on an industrial gas turbine high-pressure turbine blade. Local film effectiveness measurements were made using a pressure sensitive paint (PSP) technique by the mass transfer analogy. The two test platforms have the same size film holes at the same location to provide cooling to simulate the leakage flow in front of the platform. Six cooling mass flow ratios (MFR, blowing ratio) were studied for each of the platform test models and two-dimensional film effectiveness distributions were measured. Then the film effectiveness distributions were shown pitchwise and streamwise for comparison. In general, the leakage flow film effectiveness increases with the mass flow. Although the pattern of the film effectiveness distribution is quite different, the dolphin nose profile resulted in a slightly higher overall film effectiveness. Further study is necessary to reveal the secondary flow patterns for the platform profiles and its relation to the measured film effectiveness.

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