14th European Conference on Turbomachinery Fluid dynamics & Thermodynamics
Low-Pressure Turbine (LPT) efficiency has a direct impact on the overall system performance and so its careful design and performance prediction is of paramount importance. At the same time, the demand for lighter aeroengines has led LPT designs towards highly loaded profiles. The suction surface of these profiles is, then subject to large adverse pressure gradients, making them very sensitive to Reynolds numbers. Further, LPTs operate under a wide range of Reynolds numbers: between a few hundreds of thousands at take-off and a few tens of thousands during high-altitude cruise. The aerodynamic behavior of the profile can change dramatically throughout this range of Reynolds numbers and, hence, the profile aerodynamic loss. Taking into account that aerodynamic profile loss can account for up to 80% of the LPT efficiency, it is clear that the prediction and understanding of the loss behavior with Reynolds number is of critical importance. Wall-resolved LES has proved to be a suitable tool to predict performance of LPTs. In particular, a complete set of experiments at an array of Reynolds numbers and reduced frequencies has been reproduced with a High-Order Flux Reconstruction method LES tool. Both mean profiles and RMS of velocity fluctuations reproduced experimental results. In the work presented here the accuracy of these simulations is assessed.