It is well known that the replacement of a round tubes to an oval tube in a fin-and-tube heat exchanger reduces an air-side pressure drop as well as a low performance region behind the tube, and improves the thermal performance of the heat exchanger. However, experimental evidences are lacking, especially for generic heat exchangers. In this study, three generic samples with oval tubes were obtained and tested under wet condition. The samples had different oval tube dimensions and tube pitches. One interesting result was that the highest j factor was obtained at a two row configuration. Possible explanation was provided considering the effect of fin efficiency. The wet surface j factors were slightly lower and the wet f factors were significantly higher than those of the dry surface, probably due to the condensate on the fin surface. A thermal performance comparison (based on the conductance per unit volume (η_oh_oA_o/V_o) to the pressure drop per unit length (ΔP/L)) revealed that, the oval tube samples yielded higher performances than the round tube samples with some exceptions at a large number of tube row. Furthermore, it was found that the oval tube geometry is more effective under wet condition than under dry condition. Correlations were developed, which predicted all the j factor and 98% of the f factor within ±20%.

众所周知，在翅片管式热交换器中将圆形管替换为椭圆形管可减少空气侧压降以及管后的低效区域，并改善热量的热性能。交换器。但是，缺乏实验证据，特别是对于通用热交换器。在这项研究中，获得了三个带有椭圆管的普通样品，并在潮湿条件下进行了测试。样品具有不同的椭圆管尺寸和管间距。一个有趣的结果是，在两行配置中获得了最高的j因子。考虑到散热片效率的影响，提供了可能的解释。湿表面j因子略低，湿表面f可能是由于翅片表面的冷凝水，导致这些因素显着高于干燥表面的因素。热性能比较（基于每单位体积（电导η _ö ħ _ö甲_ø / V _ø）每单位长度上的压力降（Δ P /大号））显示，在椭圆管样品产生比轮更高的性能大量试管排中有一些例外的试管样品。此外，发现椭圆管的几何形状在潮湿条件下比在干燥条件下更有效。建立了相关性，可以预测所有j因子和98％的f因子在±20％之内。