摘要
为了研究不同射流孔形状对气膜冷却效率的影响,基于控制容积法,采用Realizablek-ε模型,对圆孔、簸箕孔和圆锥孔3种孔形的平壁气膜冷却进行了数值模拟。讨论了反向涡旋对和射流附壁性对冷却效率的影响,总结了3种形状射流孔的冷却效率随射流速度比的变化趋势。结果表明,在相同射流速度比时,簸箕孔的冷却效率和横向覆盖宽度都大于圆孔和圆锥孔,且簸箕孔的射流速度比在所计算的射流速度比范围内存在一个最佳值;簸箕孔和圆锥孔不同程度地抑制了反向涡旋对的产生,提高了射流的附壁性,从而降低了涡旋强度,增强了壁面的冷却效果。
To investigate the effects of jet hole shape on film cooling effectiveness, the flat plate film cooling using respectively three different shaped jet holes had been numerically simulated, based on control volume method and Realizable k-e model. The effects of counter rotating vortex pair and the jet-to-plate distance on film cooling effectiveness have been discussed. And the change trend of cooling effective- ness with the change of jet-to-crossflow velocity ratio had been summarized. The results suggest that the film cooling effectiveness and cooled area of dust-pan shaped hole are superior to round hole and cone shaped hole, and it has a optimal jet-to-crossflow velocity ratio. The outspread hole can decrease the jet- to-plate distance, reduce the vortex intensity, then enhance the film cooling effectiveness.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2006年第17期112-116,共5页
Proceedings of the CSEE
基金
国家自然科学基金项目(50476037)~~
关键词
热能动力工程
气膜冷却
数值模拟
簸箕形孔
圆锥形孔
thermal power engineering
film cooling
numerical simulation
dust-pan shaped hole
cone shaped hole
