气膜出流条件下回转通道换热特性实验研究

为了研究气膜出流对回转通道的影响,将回转通道的一个壁面在出口通道上开气膜出流孔,其中回转通道为带有90°直肋的变截面通道。并且将通道分成若干特征单元进行结果分析。结果表明:气膜出流加强了带气膜出流孔壁面的换热,减弱了相对的无气膜出流孔壁面的换热。而且对于整个单元而言,存在最佳的出流流量比使单元的整体换热效果最好。

An experimental study of heat transfer characteristics in a turn-over channel with ribs and film cooling

Experiment was carried out to study the influences of film cooling outflow to the internal heat transfer of a U-turn channel with variable cross-sections. Film cooling holes were distributed along one of the channel surfaces and rib turbulators were also installed. Experimental data were analysed by dividing the channel into a number of typical sections. Several conclusions may be drawn from experimental analysis that: (1)film cooling outflow enhances the heat transfer of the surface with outflow holes, (2)the heat transfer of its opposite surface without film cooling holes is reduced, (3)there exists an optimum ratio of film cooling flowrate to that of the main channel for the best heat transfer effects.