摘要
提出一种新型气膜冷却叶片结构,旨在通过反曲率设计减少冷气射流与主流的掺混作用,控制和优化掺混后的流场结构。建立了不同喷射角度的叶片三维实体模型,研究了不同喷射角度下新型叶片的气动性能、冷却效率,结果表明30°角喷射时气动效率最高,且冷却效率也较好。对比分析了冷气分布可知新型叶片中,冷气射流可很好地填补反曲率造成的空缺进而完善气动边界。详细分析了冷却孔附近的流动结构,结果表明气膜冷却射流进入主流区后受到明显抑制,没有形成典型的肾形涡,与主流的掺混作用大大减少,仅限制在壁面附近与相邻冷气射流相互干扰形成新的涡流结构。
By means of reverse curvature method, a new film cooling blade structure, which weakens the mixing process of cooling gas and mainstream, has been put forth to control and optimize the flow field structure. The aerodynamic performance and cooling efficiency are investigated in the presence of a series of different injection angle in three- dimensional models. It is shown that the aerodynamic performance is at its maximum with good cooling efficiency when the injection angle is 30 deg. Comparing the cooling air distribution between the new and the original, it indicates that the cooling gas can perfectly fill the cove made by reverse curvature method to form the aerodynamic boundary. Detailed analysis of flow structure near the cooling hole suggests that the kidney vortex is destroyed in this new type blade, the interaction between coolant jet and main stream is decreased, and only a new vortex is generated near the blade wall in the region between two neighboring holes.
出处
《汽轮机技术》
北大核心
2013年第6期401-404,共4页
Turbine Technology
基金
"国家科技支撑计划课题"
课题编号:2011BAA07B04
关键词
切向射流
气膜冷却
冷却效率
流场结构
tangential
film cooling
cooling efficiency
flow structure
