冲孔球凸/球凹翅片强化传热研究

Study on Heat Transfer Enhancement of Perforated Dimple/Protrusion Fin

为了提高多孔翅片的换热性能,本文提出了新型冲孔球凸/球凹翅片结构。采用数值模拟方法对其流动传热特性进行研究,并对冲孔球凸和冲孔球凹结构布置方式进行了优化。研究结果表明:冲孔球凸/球凹翅片形成局部射流和增加涡结构破碎,增强扰流,增强换热。在相同雷诺数Re下,冲孔球凸/球凹翅片综合换热性能明显优于多孔翅片,性能评价指标PEC提高了31.3%~55.0%;合理的布置方式可以更好地提高翅片换热性能,同时布置冲孔球凸和冲孔球凹两种结构的翅片换热性能优于单一布置冲孔球凸或冲孔球凹结构;翅片壁面同时布置冲孔球凸和冲孔球凹结构时,顺排布置优于叉排,而翅片壁面仅单一布置冲孔球凸或冲孔球凹结构时,叉排布置优于顺排。

In order to improve the heat transfer performance of porous fins,the novel perforated dimple/protrusion fins are presented in this paper.The flow and heat transfer characteristics of perforated dimple/protrusion fins are analyzed by numerical simulation method and its arrangement are optimized.The results show that the perforated dimple/protrusion fins enhance heat transfer due to the formation of local jet and the increase of vortex structure broken enhance the turbulence.The heat transfer performance of the perforated dimple/protrusion fins are superior to the porous ones under the same Reynolds number,with the comprehensive performance evaluation criteria(PEC)increases by 31.3%~55.0%.The heat transfer performance of the perforated dimple/protrusion fins can be improved better by the reasonable arrangement of perforated dimple and perforated protrusion.The fins with both perforated dimple and perforated protrusion structures have advantages over the one with either of two structures.The alignment arrangements are better than the staggered ones for the fins with both perforated dimple and perforated protrusion structures,while the staggered arrangements are better than the alignment ones for the arrangements with either of two structures.