Abstract The work deals with a thermodynamic analysis of finned liquid-gas cross-flow heat exchangers. Analyzing such devices, it is important to determine the heat transfer coefficients on the liquid and the gas side. The analysis basic problem is determination of the of the heat transfer coefficient from the finned surfaces to the flowing gas due to a non-uniform flow of gas through the exchanger. The form and the scope of the gas inflow maldistribution were determined experimentally for two different fins, cross-flow heat exchangers with elliptical tubes. Six Nusselt number correlations were selected and were used to calculate the heat transfer coefficients for measured data. The values of heat transfer coefficient were also computed based on numerical simulations using numerical models of repetitive fragments of the tested heat exchangers. The Wilson plot method was also used. The heat transfer coefficient values were put into an in-house computer code and the experiments were simulated numerically. The comparison of experimental and computational data makes it possible to evaluate different methods of the heat transfer coefficient determination. The simplest Berman correlation for the Nusselt number as well as the computational fluid dynamics based approach gave the best results.

中文翻译：

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传热系数确定方法对非均匀介质流入下翅片管错流换热器运行模拟的影响

摘要 这项工作涉及翅片液-气错流换热器的热力学分析。分析此类设备时，确定液体和气体侧的传热系数非常重要。分析的基本问题是确定从翅片表面到流动气体的传热系数，这是由于气体通过交换器的不均匀流动。气体流入分布不均的形式和范围是针对两种不同的翅片、椭圆管错流换热器通过实验确定的。选择了六个 Nusselt 数相关性并用于计算测量数据的传热系数。传热系数的值也基于使用测试热交换器的重复片段的数值模型的数值模拟来计算。还使用了威尔逊绘图方法。将传热系数值放入内部计算机代码中，并对实验进行数值模拟。实验数据和计算数据的比较使得评估传热系数确定的不同方法成为可能。Nusselt 数的最简单的伯曼相关性以及基于计算流体动力学的方法给出了最好的结果。