Thermal performance evaluation of shaped sweeping jet film cooling at simulated engine condition using emissivity-corrected infrared thermometry

Sweeping jet (SJ) is a periodic, self-excited flow generated by a fluidic oscillator, showing promising potential for film cooling applications. With continuous structural improvements, the shaped sweeping jet (SSJ) design has achieved a proper size and demonstrated excellent film cooling performance at low-speed conditions. However, its overall cooling effectiveness at engine-relevant conditions remains to be fully validated. This study investigates the thermal performance of the SSJ compared to the baseline 777 hole at simulated engine conditions. Experiments were conducted on a high-pressure guide vane with a row of SSJ on both the pressure and suction surface. Emissivity-corrected infrared (IR) thermometry was employed to measure the vane surface temperature across several blowing ratios (0.5 <= M <= 3.0), providing an evaluation of overall cooling effectiveness. This method incorporates three-dimensional reconstruction and emissivity correction to address temperature measurement errors caused by directional emissivity. The results indicate up to a 42 % improvement in overall cooling effectiveness for the SSJ compared to the baseline 777 hole, further validating the SSJ film cooling at simulated engine conditions and highlighting its potential for advanced turbine cooling applications.