The effect of inlet wake and air injection on blade surface temperature distribution is experimentally determined in the present paper. A flat plate with smoothly curved leading edge and a symmetric beveled trailing edge is used to produce inlet wake. Experiments are performed on a seven-airfoil linear cascade in a low speed wind tunnel at the chord Reynolds number of 5.3x10~5. Three blades in the middle of the cascade are provided with multiple rows of air injection holes on both pressure surface and suction surface. The distance between the trailing edge of the wake plate and leading edge of the cascade blade is kept at three axial locations, i.e. 0.25, 0.35 and 0.5 (all measured in terms of percent blade chord), at seven transverse locations for each axial location. The detailed temperature distributions on the blade surface are measured using "T-Type" thermocouples connected to a data logger. The results are obtained in terms of film cooling effectiveness for a density ratio (between the hot fluid through air injection holes and cold main flow fluid) of 1.1 and injection mass flow rates of 1.1, 2.5, 3.0 and 5.0 percent of main flow. A significant change in the film cooling effectiveness is observed with increase in the injection mass flow rate and change in the axial spacing.
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