Study on Heat Transfer Enhancement of Perforated Dimple/Protrusion Fin

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.