Experiments and CFD based design and analysis of a novel indirect evaporative cooler for future sustainability

A notable substitute for traditional vapor compression chillers that is economical, sustainable, and energy-efficient is indirect evaporative cooling (IEC) technology. It offers several advantages like resource saving (energy, water, emissions, etc.), environmentally friendly working, and chemical-neutral operation. However, IEC systems are still in the development stage and require significant improvements in design and materials to outperform the market-dominant vapor compression chillers. This work offers a thorough experimental and computational fluid dynamics (CFD) investigation of an innovative cooling system that overcomes significant design constraints and provides improved performance. The proposed system's 150 W cooling capacity is fabricated and studied. Then, a robust model is developed to examine the impact of key input parameters, such as temperature, velocity, channel length, and airflow rate ratio. The CFD model is rigorously validated with the existing literature and the current experimental data. The experiment revealed a temperature reduction of 20.4 °C for an outside air temperature of 48 °C. The CFD analysis shows that increasing dry and wet channel velocities (1–3 m/s) slightly increased the supply temperature, indicating design constraints on cooling capacity. Meanwhile, an increase in the airflow rate ratio (AFR) lowers the supply air temperature because a higher AFR boosts evaporation in the wet channel, thereby increasing heat transfer. Furthermore, it is noted that latent heat transfer during evaporation accounts for most of the cooling, resulting in a temperature reduction of up to 20 °C in the dry channel compared to just a 3 °C (max) rise in the working air temperature.