This paper investigated the flow and heat transfer characteristics of traditional single-stage and multi-stage impingement cooling structures using numerical simulation methods.The results show that the crossflow in the multi-stage impingement restarts accumulating in each stage of the impingement chamber,which inhibits the development of the crossflow and effectively reduces the detrimental effect of the crossflow on the downstream heat transfer.Under a same Reynolds number condition,the multi-stage impingement structures save substantially on coolant usage,and the two-stage impingement brings an 11％enhancement to comprehensive heat transfer performance,proving that the multi-stage impingement has a significant thermal benefit.Under a same coolant flow rate condition,the multi-stage impingement structures have higher Reynolds numbers,which improves the overall heat transfer effect of the target surface.The two-stage,three-stage,and four-stage impingement structures can bring 1.8,2.3,and 2.6 times of heat transfer enhancement to the target surface,respectively,but pumping power and total jet inlet pressure are also higher,resulting in a decrease in comprehensive heat transfer performance with an increasing number of stages.
关键词
冲击冷却/多级冲击/换热特性/流动特性/综合换热性能
Key words
impingement cooling/multi-stage impingement/heat transfer characteristic/flow characteristic/comprehensive heat transfer performance
维普
万方数据