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本文通过数值模拟方法对四排管叉排布置的小型平直翅片管束的传热和阻力性能进行了研究,分析了边缘效应对小型翅片管束传热和阻力性能的影响,结果表明,6-6-6-6布管方式优于6-5-6-5布管方式,在只有较少换热管的小型翅片管换热器中,边缘效应不可忽略,实际整体模型的阻力系数比文献中常用的简化对称模型小13%~14%,努塞尔数小15%~18%,本文提出的公式可用于快速而准确地估算小型平直翅片管束的努塞尔数和阻力系数.
In this paper, the heat transfer and resistance performance of small flat finned tube bundles arranged in four rows of tubes were studied by numerical simulation. The influence of edge effect on the heat transfer and the resistance performance of small finned tube bundles was analyzed. The results showed that 6 -6-6-6 is better than the 6-5-6-5 pipe delivery method. In the small finned tube heat exchanger with fewer heat exchange tubes, the edge effect can not be neglected. The drag coefficient of the actual overall model Which is 13% -14% smaller than the simplified symmetrical model commonly used in literature and 15% ~ 18% smaller than that of Nusselt. The formula proposed in this paper can be used to quickly and accurately estimate the Nusselt number and resistance of small flat finned tube bundles coefficient.