摘要
透平叶片的冷却技术是提高燃气轮机效率的关键,其中气膜冷却是非常重要的一种冷却方式。参考某型燃气轮机第一级动静叶片的几何尺寸进行建模,采用数值模拟的方法对气膜冷却进行了分析研究,主要研究了叶片前缘的气膜冷却。分析比较了多种参数对气膜冷却效果的影响,即不同吹风比、密度比、自由流湍流度和射流角度的影响。结果显示:吹风比过大或过小,冷却效果都不好;高密度的射流比低密度的射流更容易保持在表面处;低湍流度比高湍流度时气膜冷却有效度更佳;适当调整射流角度能改善冷却效果。
Turbine blade cooling technologies are very important to the improvement of gas turbine efficiency, among which film cooling is one of the key ways. According to the geometry of the first-stage moving and stationary blade of a certain type of gas turbine, a blade model was set up, based on which numerical simulation was conducted to analyze the film cooling technology, with focus on leading-edge film cooling, so as to study the effects of following factors on the film cooling efficiency, such as the blowing ratio, density ratio, free stream turbulence and the jet angle, etc. Results show that poor cooling effect will be resulted if the blowing ratio is too high or too low; high-density jet stream can be maintained more easily on the surface than low-density stream; better film cooling effect can be obtained under lower but not higher turbulence conditions; the cooling effect can be improved by reasonably adjusting the jet angle.
出处
《发电设备》
2015年第1期11-14,23,共5页
Power Equipment
关键词
叶片
气膜冷却
数值模拟
影响因素
吹风比
冷却效率
blade
film cooling
numerical simulation
influence factor
blowing ratio
cooling efficiency
