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采用大涡模拟研究抑涡孔气膜冷却的流动和换热机理.通过与相同工况下圆孔气膜冷却流场的湍流结构进行比较分析,得出辅孔射流与主孔射流之间的干涉作用,并探索大尺度湍流结构影响气膜冷却效率的物理机制.结果表明:①辅孔射流抑制主孔射流形成的反转涡对的尺寸和强度,并为主孔射流的卷吸提供冷气补充;②由于上游辅孔出流冷气的保护作用以及对主孔出口尾缘低压区的冷气补充作用,主孔射流在气膜孔出口处温度没有急剧升高;③由于辅孔射流的干涉作用,主孔射流并未形成完整的发卡涡结构,而是无规律的近壁条带结构,减少了冷气和主流的掺混,并使冷气更好覆盖和冷却壁面.
The large-eddy simulation is used to study the flow and heat transfer mechanism of the eddy-bubble film cooling. By comparing with the turbulent structure of the film cooling flow field under the same conditions, the relationship between the sub-hole jet and the main jet And the physical mechanism of large-scale turbulence structure affecting the cooling efficiency of the film was explored.The results showed that: (1) The auxiliary jet suppressed the size and strength of the reversed vortex formed by the main jet and provided air-conditioning for entrainment of the main jet Supplement; ② Because of the protective effect of the outflow cold air from the upstream auxiliary hole and the cold air supplement to the low pressure zone at the trailing edge of the main hole, the temperature of the main hole jet at the outlet of the film hole does not increase sharply; ③ Due to the interference of the auxiliary hole jet, The main jet does not form a complete hairpin vortex but a random near-wall strip structure, which reduces the air-to-air mixing and allows the air to cover and cool the wall better.