肋片扰流对柱肋通道传热和压损影响

针对涡轮叶片内部通道上、下游不同冷却结构的相互影响,采用瞬态液晶实验方法研究了上游90°、60°,V形和W形四种肋片诱导产生的入口条件,对柱肋通道传热分布、强化传热水平和压损的影响,并与无肋片(均匀入口条件)的柱肋通道进行了对比。结果表明,相比于无肋片情况的均匀入口条件,肋片诱导的涡流使柱肋通道底面的传热分布在展向变得不均匀。肋片在增强柱肋底面传热的同时降低了通道压损,从而提升柱肋通道的综合换热效率(但整体通道的流动损失增加了)。其中,W形和90°肋片使柱肋通道具有最高的传热效率,其次是V形和60°肋片,不带肋片的情况的综合传热效率最低。 

Rib influence on heat transfer and pressure drop in pin-fin array

For the interaction between diverse internal cooling structures in turbine blades, various shaped ribs’ influences on pin-fin array heat transfer and pressure drop were investigated using a transient liquid crystals test. The 90°, 60°, V-shaped and W-shaped ribs were considered to compare the characteristic differences of pin-fin array heat transfer distribution, heat transfer enhancement and pressure drop levels. The results showed that upstream ribs made the spanwise variation of pin-fin endwalls heat transfer non-uniform. The vortices induced by upstream ribs appeared to enhance pin-fin array heat transfer but reduce pressure drop, leading to an overall thermal efficiency improvement. The W-shaped and 90° ribs made pin-fin arrays yield the best thermal efficiency and then the V-shaped and 60° ribs.