涡轮叶片全表面换热特性试验研究

Study on Full Surface Heat Transfer Characteristics Test of Turbine Blade

气冷叶片表面对流换热系数对气冷叶片设计至关重要。为了研究气冷叶片表面对流换热特性,设计了典型气膜冷却叶片,采用试验与数值计算相结合的方法对气冷涡轮叶片表面流动换热特性进行了对比研究,获得了叶片表面温度场及叶栅通道内部流场分布特征。结果表明:叶片表面的换热受叶栅流道结构的影响较大。在叶片前缘滞止点以及主流加速剧烈的位置换热较强,加入气膜孔可以局部增强叶片表面的对流换热,但却没有改变叶片全表面换热的变化趋势。

The convective heat transfer coefficient on the surface of air-cooled blade is very important to the design of air-cooled blade.In order to study the convective heat transfer characteristics on the surface of film cooling blade,a typical film cooling blade was designed.The flow and heat transfer characteristics on the surface of air-cooled turbine blade were compared and studied by means of test and numerical calculation.The temperature field on the blade surface and the distribution characteristics of the flow field were obtained in the cascade channel.The results show that the heat transfer of the blade surface is affected by the structure of the cascade channel.The heat transfer is stronger at the stagnation point of the front edge of the blade and at the position where the mainstream acceleration is intense.The convective heat transfer on the blade surface can be locally enhanced by adding the film hole,but it does not change the changing trend of the full surface heat transfer of the blade.