SENSITIVITY ANALYSIS OF SUPERSONIC TURBINE TRAILING EDGES

The use of compact architectures on aircraft turbine engines challenges the design and management of structural and thermal load requirements. Even operating in subsonic conditions, supersonic regimes may develop at the high pressure turbine passages,
experiencing complex compression and expansion wave systems that interact with adjacent stages of the turbine. When cooling
flow is ejected through the blade trailing edge slots, non-symmetrical con gurations can appear due to the interaction of the injected flow with the surrounding flow eld, leading to undesired loads and eciency loses.
In this work, a combination of RANS simulations, global stability and sensitivity analysis is employed to identify and explain the physical mechanisms of this phenomenon. A global mode associated with the geometrical expansion of the trailing edge slot is identified, and linked to the non-symmetrical con gurations. To conclude, the regions where the flow would be more sensitive to flow modifications to excite or damp this phenomena are identied throughout an adjoint approximation.