IMPACT OF LEAN ON AERODYNAMIC PERFORMANCE OF A TURBINE REAR STRUCTURE

Paper i proceeding, 2024

Jet engine components typically have constraints from multiple disciplines that impact their design. One such component is the Turbine Rear Structure (TRS), situated aft of the Low-Pressure Turbine (LPT) in a jet engine. Due to constraints, some TRSs have vanes with large lean angles up to 30 degrees, with the pressure side leaning towards the hub. Both experimental and numerical studies are conducted to evaluate the impact of large lean angles on the aerodynamics of a TRS. The test facility provides engine-realistic Reynolds numbers and inlet swirl profiles for a TRS. The instrumentation and experimental methods employed in the rig are presented. The experimental results provide valuable data for validating numerical methods used in industry. The validation efforts revealed that today's numerical methods can effectively predict most of the physical phenomena observed in the measurements with leaned vanes. Following a comprehensive validation of the numerical methods, a study was initiated to understand the aerodynamic distinctions between a radial vane design and a leaned vane design operating under the same flow conditions. A radial vane design was created by eliminating the lean angle from a leaned vane design without applying any further changes to other parameters. This modification resulted in a static pressure decrease on the pressure side at the hub. Additionally, comparing leaned vanes and radial vanes, the results show that the vortices tend to migrate locally and hence loss redistribution occurs near the hub.