基于正交试验和Fluent的管翅式换热器结构优化

通过正交试验和数值模拟相结合的方法研究平直翅片管式换热器的换热和流阻特性，以换热系数和压降作为评价指标，用逐个分析各参数对换热和流阻特性的影响以及综合换热评价指标两种评价方法实现对换热器风机风量、翅片间距、厚度和管横纵向间距的优化。结果表明：翅片间距对压降影响最大，管纵向间距对空气侧换热系数影响最大；一种优化组合为风机风量1 450 m³/h、翅片间距2.4 mm、翅片厚度0.38 mm、管横向间距28 mm和纵向间距15 mm，另一种优化组合为风机风量1 700 m³/h、翅片间距2.4 mm、翅片厚度0.38 mm、管横向间距28 mm、纵向间距21 mm；使用优化换热器的冰淇淋机的换热能力比原设备分别提高了5.73%和6.85%。

Structure optimization of a finned-tube heat exchanger based on orthogonal tests and Fluent

Orthogonal tests and numerical simulation have been employed to investigate the heat transfer characteristics and flow resistance of a plate finned-tube heat exchanger, as well as the heat transfer coefficient and pressure drop. By individual analysis of the influence of each parameter on the heat transfer, flow resistance and comprehensive heat transfer evaluation index, this paper use two different approaches to optimize the wind volume of the fan of the heat exchanger, the fin spacing, the fin thickness and the horizontal and vertical spacings. The results show that the fin spacing has the most significant effect on pressure drop, and the vertical spacing between tubes has the greatest effect on the airside heat transfer coefficient. One optimization is a fan air volume of 1 450 m³/h, fin pitch of 2.4 mm, fin thickness of 0.38 mm, transverse spacing of the pipe of 28 mm, and vertical spacing of the pipe of 15 mm; the other optimization is a fan air volume of 1 700 m³/h, fin pitch of 2.4 mm, fin thickness of 0.38 mm, transverse spacing of 28 mm, and vertical spacing of 21 mm. By using the two optimized heat exchangers, the heat transfer capacity of an ice cream machine can be increased by 5.73% and 6.85%, respectively.