Effects of the Slotted-Cavity Tip on the Vortices and Aerothermal Performance in the High-Pressure Turbine

Abstract

To enhance aerodynamic performance in high-pressure turbines, cavity tips are commonly employed. However, these cavity tips tend to generate more vortices than flat tips, leading to an increased thermal load on the blade tips. This study introduces a novel configuration aimed at suppressing vortex intensity by incorporating a slot at the cavity bottom. Through numerical simulations, the impact of slot geometry parameters on vortices and aerothermal performance is investigated. The findings reveal that a slot height of 0–0.1 mm effectively suppresses the pressure side corner vortex within the cavity, while a slot height of 0.2–0.3 mm eliminates it. A slot height of 0.3 mm reduced average heat transfer and the high heat transfer region at the cavity bottom by 22.6% and 92.6%, respectively; however, it was observed that the leakage flow increased by 15.9%. Therefore, this study further combines the slot structure with a winglet to control the leakage flow. The combined structures exhibit superior overall performance compared to the single-slot cavity tip. Compared to the conventional cavity tips, the combined structure achieves a maximum reduction of 27.3% in average heat transfer and 7.9% in leakage flow, along with a decline of 1.9% in total pressure loss.