Abstract A numerical investigation was conducted to determine the effects of fin shape on heat transfer coefficients during in-tube condensation of R410A. Four micro-fin tubes of different geometries were selected for this study, including a straight-finned one and three helical tubes, and two different helical angles of 18° and 31° were included to explore the influence of helical angles. The numerical results were verified by previous experimental results. It was found that there was a positive relationship between heat transfer coefficients and mass velocities and vapor quality, while the helical angle seemed to improve the heat transfer coefficients especially for medium vapor quality. A nearly symmetrical liquid film distribution was found along the circumference for all three micro-fin tubes due to the centrifugal force, while the liquid tends to accumulate at the bottom of the straight-finned tube.

中文翻译：

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不同几何形状微翅片管中对流冷凝的数值研究

摘要 为了确定翅片形状对 R410A 管内冷凝过程中传热系数的影响，进行了数值研究。本研究选择了四种不同几何形状的微型翅片管，包括直翅式一管和三螺旋管，并包括 18° 和 31° 两种不同的螺旋角来探讨螺旋角的影响。先前的实验结果验证了数值结果。发现传热系数与质量速度和蒸汽质量之间存在正相关关系，而螺旋角似乎可以提高传热系数，尤其是对于中等蒸汽质量。由于离心力，所有三个微翅片管的圆周上都发现了几乎对称的液膜分布，