At present, there is great interest in indirect evaporative coolers (IECs), which can be effectively used to increase energy efficiency of HVAC systems, with particular attention to data center applications. In such devices, performance significantly depends on the formation of an adequate water layer on heat exchanger plates. Therefore, efforts should be made to promote water spreading through an appropriate design of the system.

In this study, an experimental analysis of IECs manufactured with heat exchangers having different geometry is carried out. The scope of the research is to investigate the effect of different plates protrusion and pitch on IEC wet bulb effectiveness and pressure drop. Tests are carried out with counter and parallel air and water flow arrangement.

Results highlight that plates geometry influences both surface wettability and the heat transfer rate. A reticular plates protrusion appears to be a good compromise to enhance system effectiveness. Tests also highlight that the parallel water and secondary air flows arrangement leads to higher wet bulb effectiveness and lower pressure drop compared to the counter flow configuration.

当前，人们对间接蒸发冷却器（IEC）非常感兴趣，它可以有效地用于提高HVAC系统的能源效率，尤其是对数据中心应用的关注。在这种装置中，性能很大程度上取决于在热交换器板上形成足够的水层。因此，应努力通过适当的系统设计来促进水的扩散。

在这项研究中，对采用不同几何形状的热交换器制造的IEC进行了实验分析。研究的范围是研究不同板的突出和间距对IEC湿球有效性和压降的影响。测试采用反向和平行的空气和水流布置进行。

结果表明，板的几何形状会影响表面润湿性和传热速率。网状板突出似乎是增强系统有效性的良好折衷方案。测试还强调，与逆流配置相比，平行的水流和二次空气流布置可导致更高的湿球效率和更低的压降。