流向微肋气膜冷却布局对涡轮动叶凹槽状叶顶传热冷却性能的影响OA

[Objectives]To enhance the heat transfer and cooling performance of blade tips and explore how curved micro-ribs induce cooling air flow and affect heat transfer performance,this study uses a numerical solution of three-dimensional Reynolds averaged Navier-Stokes(RANS)equation and standard k-ω turbulence models.The effects of streamwise micro-rib film cooling arrangements on heat transfer and cooling performance of cavity turbine blade tips are analyzed.[Methods]Based on the cavity blade tip of the first stage in GE-E3 high-pressure turbine,and following previous experience,a film cooling arrangement(case 1)is designed with large-diameter film holes at the leading and trailing edges,and two small-diameter film holes near the pressure side at the mid-chord region.Then,two additional small-diameter film holes are added near suction side at the mid-chord region where cooling air is scarce,and four mid-chord film holes are arranged at three positions to investigate the effect of hole position.For these three cooling arrangements,a curved micro-rib with 30％arc length is added to explore the effect of rib structure.[Results]Compared to case 1,placing the micro-rib at the leading edge of the cavity reduces blade tip leakage flow by 0.9％and total pressure loss at the outlet cross-section of flow passage by 0.5％.Positioning the micro-rib near the trailing edge results in an 8％reduction in blade tip heat transfer coefficient,and a 16％reduction when the micro-rib surface is excluded.Additionally,the streamwise micro-rib film cooling arrangement at this position achieves a film cooling effectiveness of 0.43 and optimal cooling uniformity.[Conclusions]The research findings can provide valuable references for the coupled design of high-performance blade tip structures in gas turbines;Reynolds averaged Navier-Stokes equation