Experimental study on the low-pressure turbine wake interaction and development in the turbine rear structure

Paper i proceeding, 2022

The aerodynamic characteristics of advanced turbine rear structures (TRSs) could be affected by the interaction between unsteady flow developed from low-pressure turbine (LPT) and outlet guide vanes (OGVs). Consequently, analyzing the details of the interactions between the rotor wakes, stator wakes and OGVs is essential to enhance the aerodynamic efficiency of the modern TRS. This paper presents time resolved flow field measurements in the TRS at engine representative flow conditions. Experiments were performed in an annular large-scale 1.5 stage turbine facility at Chalmers University of Technology, Laboratory of Fluid and Thermal Sciences. The facility provides engine-realistic boundary conditions for the TRS and experimental data were acquired using 5-hole and 7-hole probes (5HP and 7HP), hot-wire anemometry (HW) and Particle Image Velocimetry (PIV). The PIV and HW measurements were conducted for the first time to enhance the understanding of unsteady flow phenomena and to investigate the development of TRS inflow structures. The observed unsteady interaction mechanism between the rotor wakes, stator wakes and OGV is of prime interest and investigated in detail. The breakdown of rotor and stator wakes through the TRS are documented and the OGV wake is analysed in detail by PIV.