Development and performance analysis of a compact counterflow dew-point cooler for tropics

•A compact counter-flow indirect dew-point evaporative cooler.•Working air to flow from the dry to wet channels without changing its direction.•The cooling capacity and COP are 440–930 W and 6–51, respectively.•Cool and fresh air to improve air ventilation and mitigate airborne disease risk. Mechanical vapor compression coolers have dominated air conditioning systems since the invention of the refrigerant cycle. However, disadvantages such as huge energy consumption and environmental pollution are becoming increasingly prominent. Additionally, amid the Covid-19 pandemic, concerns have grown that current air conditioning systems can increase the spread of airborne diseases by circulating indoor air. In other words: a supply of fresh indoor air is necessary. Therefore, there is a need to develop alternative technologies. Among alternative technologies, dew point evaporative cooling technology is considered ideal due to its advantages. This paper reports the development of a compact air cooler based on a new method of indirect counterflow dewpoint evaporative cooling. A key component of this cooling system is the counterflow heat exchanger, which allows a portion of the air to flow from the dry channel to the wet channel without changing its direction. This results in uniform air flow and low pressure drop within the cooler's channels, resulting in high cooling efficiency, high cooling capacity, and high energy efficiency. The developed air cooler was tested in tropical weather conditions. The results show that within the air volume test range, the wet bulb efficiency, cooling capacity, and refrigeration COP are 85–114 %, 440–930 W and 6–51 % respectively. It is a sustainable solution that cools air by 3–7 °C and provides 100 % fresh air to improve indoor ventilation and reduce the risk of airborne diseases, including the Covid-19 virus.