Enhancement of Natural Convection Heat Transfer From a Fin by Triangular Perforations of Bases Parallel and Toward Its Tip
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摘要: 研究一种设置水平矩形翅片对自然对流传热的强化作用,翅片内含三角形穿孔,三角形的底边平行并朝向翅片顶端.比较了这种多孔翅片和同等实心翅片的热耗散率.考虑的参数包括翅片及其穿孔的几何尺寸和热性能.讨论了翅片穿孔后引起的传热强化和翅片重量的减轻.结果表明,在某些三角形穿孔和穿孔间距的值域内,穿孔翅片改进了同等情况实心翅片的热耗散.当翅片导热率及其厚度增大时,穿孔翅片的传热也强化.Abstract: Heat transfer enhancement from a horizontal recrtarrgular fin embedded with triangular perforations (their bases are parallel and toward to the fin tip) under natural convection is studied.Its heat dissipation rate was compared to that of the equivalent solid one.The parameters considered were geometrical dimensions and thermal properties of the fin and of the perforations.The gain in heat transfer enhancement and the fin weight reduction due to the perforations was considered.It is shown also that the heat dissipation from the perforated fin for certain range of triangular perforation dimension and spaces between perforations result in improvement in heat transfer over the equivalent solid fin.The heat transfer enhancement of the perforated fin increases as the fin thermal conductivity and its thicluress are increased.
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