Pulsating Coolant Ejection Effects Downstream of a Transonic Rounded Trailing Edge

Trailing edge blowing is used in a great variety of applications. In particular, high-pressure turbines bleed about 3% of the engine core massflow through a rear slot. At transonic conditions the coolant flow alters substantially the base region, and therefore the wake and shocks. Certain pulsating coolant frequencies give rise to exotic vortical shedding structures, not observed when the coolant is continuous. A detailed analysis of the flow field near the trailing edge region has been performed using the in-house HybFlow code. A rounded trailing edge with null and continuous blowing (at different pressure ratios) have been compared with a blunt trailing edge geometry using steady simulations. Both shock intensity, and wake loss are discussed in this paper considering pulsating coolant ejection at various frequencies and blowing ratios.