Numerical simulation of a novel energy-efficient dew-point evaporative air cooler

We present simulation results on a novel dew-point evaporative air conditioner which was designed based on a counter-flow closed-loop configuration consisting of separated working channels and product channels. The novel evaporative air conditioner is able to cool air to temperature below ambient wet-bulb temperature and approaching dew-point temperature. To investigate the performance of the evaporative air cooler under a variety of conditions, the Eulerian-Lagrangian computational fluid dynamics (CFD) model was adopted. We validated the model by comparing the temperature distributions and outlet air conditions against experimental data. The numerical model showed good agreement with the experimental findings to within ±10%. Impacts due to the inlet air condition, the air flow velocity, the dimension of the airflow passages, and the product-to-working air flow ratio on the cooler performance were analyzed. Simulation results have indicated that the novel dew-point evaporative air conditioner is able to achieve a higher wet-bulb and dew-point effectiveness with lower air velocity, smaller channel height, larger length-to-height ratio, and lower product-to-working air flow ratio.