燃气轮机透平叶片冷却通道传热特性研究进展

Review on Research of Heat Transfer Performance for Gas Turbine Blade Cooling Channel

燃气轮机透平叶片冷却通道的设计及开发对燃气轮机效率、运行安全性等具有重要意义,透平叶片冷却通道的传热特性研究是透平叶片中的重要领域。文中首先总结了透平叶片中典型U型通道中扰流冷却的研究现状:在U型通道中布置肋片、针状翅片、球窝/球凸及组合传热结构是重要的冷却方式,研究已深入至多种组合传热结构及旋转通道传热的层面;其次总结了冷却通道与气膜孔结构耦合传热的研究现状,气膜孔的布置改变了冷却通道内的原流场结构及传热特性,布置肋片、球窝等强化传热结构并与气膜孔相耦合时的流动及传热特性是目前研究的重点;最后总结了内部冷却与外部冷却相耦合时的传热特性,如叶片尾缘劈缝叶背面区域的气膜冷却与对流传热共同作用,指出该耦合传热过程是透平叶片中的重要现象。通过对透平叶片冷却通道传热特性的研究综述,指出在组合传热结构与气膜孔等相互耦合时的冷却通道传热特性还有较多的研究内容需要扩充,同时考虑适用于冷却通道的低阻高效强化传热结构也是目前关注的一大重点。

Design and development of cooling channel for gas turbine blade is of great importance for gas turbine efficiency and Safety. Research on heat transfer performance of cooling channel is important research area. The heat transfer performance of typical U-shaped cooling channel with tabulator was reviewed. Appling rib, pin-fin, dimple/protrusion or combination structures are important cooling schemes in U-shaped cooling channel. The investigation in and aboard has deepen into multiple combination structure and rotating cooling channel. Then, the coupling heat transfer effect of cooling channel and bleed hole was reviewed. The installation of bleed hole changes the original flow field and heat transfer characteristics of cooling channel. The coupling effect of rib, .dimple or other heat transfer enhancement structure with bleed hole is the key field in this research area. Finally, the investigation of coupling heat transfer performance for internal cooling and external cooling was reviewed. The film cooling and convective heat transfer, such as the trailing edge cutback surface, are combined affected which is an important phenomenon in gas turbine blade. By reviewing the research in gas turbine cooling channel, it is suggested that the research on combination heat transfer enhancement structure and coupling effect with bleed hole still need investigating more deeply. Besides this, cooling channel with efficient heat transfer augmentation structure and low pressure penalty is a focusing area in future cooling channel research.