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Abstract Future turbofan designs are expected to include gearboxes to allow for the decoupling of the fan and the low-pressure turbine. Doing so will increase overall engine efficiency, but change the design point for low-pressure turbines by allowing to increase the rotation speed. To study these new high-speed turbines, an experimental configuration from the European project SPLEEN, supported by the Von Karman Institute (VKI) and SAFRAN Aircraft Engines, is investigated using Large Eddy Simulation (LES). Three simulations based on the experimental SPLEEN cascade are performed: a baseline case without the purge flow cavity, a case with the purge flow cavity, and a case with the purge flow cavity and 0.9% mass flow rate relative to the main flow. These simulations capture engine-relevant turbulence, transition, and transonic Mach number physics that are expected in this operating regime. The losses in the cascade are analyzed and compared to experiment, showing good predictive capabilities of LES.
Perkins et al. (Mon,) studied this question.