Comparative study on dew point evaporative cooling systems with multistage configurations

Advanced dew point evaporative cooling has broken the wet bulb temperature barrier of previous technologies. Recent research demonstrated that the dew point cooling system with counter-flow configuration had the potential to achieve better effectiveness and cooling capacity. Most of the research work available in the literature focuses on the single-stage model. In this paper, therefore, we proposed the method of multistage counter-flow dew point evaporative cooling system. A mathematical model was developed to compare the performance of single-stage, two-stage and three-stage systems. The comparison was executed for assorted parameters such as product air temperature and cooling effectiveness, and the improvement of the multistage systems was quantified. It was observed that (1) a multistage system was able to achieve up to 10.2% enhancement in the system performance under various inlet air conditions, and (2) the two-stage system provided the best performance under most inlet air conditions.