摘要
透平动叶通常采用垂直横向内冷通道与气膜冷却结合的冷却结构,因此,需要考虑垂直横向冷气流动对气膜冷却流动和冷却特性的影响。以垂直横流进气条件下的简化平板气膜冷却为研究对象,采用流体计算动力学方法,对不同吹风比下常用圆柱形气膜孔的冷却和流动特性进行分析。相比于冷气腔进气条件,垂直横流进气条件下的面积平均效率在低吹风比下较小,而在中高吹风比下较大。随着吹风比的增大,孔下游冷却效率分布由单峰型转换为双峰型,孔出口近下游区域的冷却效率降低,而远下游区域的冷却效率提高,冷气射流流动和肾形涡对的非对称性随之减弱。
The combination of the film cooling and the perpendicular coolant passage is usually adopted for the gas turbine rotating blades.Thus,the cooling effectiveness and the fluid flow should be considered for the film-cooling hole with perpendicular coolant cross-flow conditions.The simplified flat-plate film cooling is selected in the study.The cooling effectiveness and the flow performance are investigated for the common cylindrical hole under different blowing ratios using a computational fluid dynamic approach.The area-averaged cooling effectiveness with perpendicular coolant cross-flow condition is lower than that with coolant plenum conditions under low blowing ratio but higher under medium-to-high blowing ratios.With the increase of the blowing ratio,the cooling effectiveness distribution is changed from a single-peak shape to a double-peak shape.The cooling effectiveness is lower in the near downstream region from the hole exit,but higher in the far downstream region.The asymmetries of the ejected coolant flow and the kidney-shaped vortex pair decrease with the blowing ratio.
作者
石淯臣
张鹏飞
李嘉欣
张超
SHI Yuchen;ZHANG Pengfei;LI Jiaxin;ZHANG Chao(Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control,Tianjin University of Technology,Tianjin 300384,China;National Demonstration Center for Experimental Mechanical and Electrical Engineering Education,Tianjin University of Technology,Tianjin 300384,China)
出处
《天津理工大学学报》
2021年第3期8-12,共5页
Journal of Tianjin University of Technology
基金
天津市自然科学基金(18JCQNJC07200)
大学生创新创业训练计划项目(202010060035)。
关键词
气膜冷却
圆柱孔
横向冷气流动
冷却效率
流动特性
film-cooling
cylindrical hole
perpendicular coolant crossflow
cooling effectiveness
flow performance
