Studying the performance of an improved dew-point evaporative design for cooling application

摘要

The performance of a novel dew-point evaporative air cooler is theoretically investigated in this paper. The novel dew-point evaporative air cooler, based on a counter-flow closed-loop configuration, is able to cool air to temperature below ambient wet bulb temperature and approaching dew-point temperature. A computational model for the cooler has been developed. We validated the model by comparing the temperature distribution and outlet air conditions against experimental data from literature. The model demonstrated close agreement with the experimental findings to within ±7.5%. Employing the validated model, we studied the cooler performance due to the effects of (i) varying channel dimensions; (ii) employing room return air as the working fluid; and (iii) installing of physical ribs along the channel length. Using these means, we have demonstrated improved performance of the dew-point cooler - enabling it to achieve higher efficiencies. Operating under variant inlet air temperature and humidity conditions, simulated results showed that the wet bulb effectiveness ranged from 122% to 132% while dew-point effectiveness spanned 81%-93%.