As continuous of the previous sand-dune-inspired design,the Barchan-Dune-Shaped Injection Compound(BDSIC)’s film cooling performance at the endwall region was further investigated both experimentally and numerically....As continuous of the previous sand-dune-inspired design,the Barchan-Dune-Shaped Injection Compound(BDSIC)’s film cooling performance at the endwall region was further investigated both experimentally and numerically.While the public 777-shaped hole was served as a baseline,the BDSIC’s endwall effectiveness was assessed at various blowing ratios.Experiments were performed in a single-passage transonic wind tunnel using pressure-sensitive paint(PSP)technique.Carbon dioxide was used as coolant with density ratio of DR=1.53.The purge slot’s blowing ratio was fixed at M=0.3,but the coolant holes were adjusted within M=0.5–2.0.The measured experimental results indicate that the film distribution at the endwall is strongly affected by the passage flow structures.The BDSIC holes demonstrate much higher film effectiveness than the 777-shaped holes for all blowing ratios,~30%enhancement for regionally averaged effectiveness at M=1.0 and~26%at M=2.0.As shown by the numerical results,the existence of BDSIC reduced the coolant penetration effect at a higher blowing ratio.Coolant was deflected and its momentum increased in the streamwise direction,therefore providing more robust film coverage over the endwall region.The anti-counter-rotating vortex pair induced by the BDSIC further stabilized the coolant film and increased the coolant spreading downstream.展开更多
基金funding supports from the NSFC(92052107,51806138)。
文摘As continuous of the previous sand-dune-inspired design,the Barchan-Dune-Shaped Injection Compound(BDSIC)’s film cooling performance at the endwall region was further investigated both experimentally and numerically.While the public 777-shaped hole was served as a baseline,the BDSIC’s endwall effectiveness was assessed at various blowing ratios.Experiments were performed in a single-passage transonic wind tunnel using pressure-sensitive paint(PSP)technique.Carbon dioxide was used as coolant with density ratio of DR=1.53.The purge slot’s blowing ratio was fixed at M=0.3,but the coolant holes were adjusted within M=0.5–2.0.The measured experimental results indicate that the film distribution at the endwall is strongly affected by the passage flow structures.The BDSIC holes demonstrate much higher film effectiveness than the 777-shaped holes for all blowing ratios,~30%enhancement for regionally averaged effectiveness at M=1.0 and~26%at M=2.0.As shown by the numerical results,the existence of BDSIC reduced the coolant penetration effect at a higher blowing ratio.Coolant was deflected and its momentum increased in the streamwise direction,therefore providing more robust film coverage over the endwall region.The anti-counter-rotating vortex pair induced by the BDSIC further stabilized the coolant film and increased the coolant spreading downstream.
