Optimizing the performance of cotton Bundle-based solar evaporative cooling system using a CFD Model: Model Development, Validation, and optimization

Abstract

A Solar Evaporative cooling system is an energy-efficient, environmentally friendly, and low-cost air conditioning system. It is an economical air conditioning system for any type of cooling application, such as cold storage of horticulture products and ventilation systems. In this work, a computational fluid dynamics CFD-based model was used to study the parametric effect and to optimize the evaporative air cooler. The system used cotton bundles for the absorption and evaporation of water. Heat and mass transfer processes were coupled using user-defined functions. The accuracy of the model was validated by the experimental results. The predicted results well agreed with experimental results; with average errors of 13.39% (pressure drop), 2.347% (supply air temperature), and 2.22% (supply air relative humidity). The effects of airspeed, porosity, and thickness of the bundle on the cooling performance of evaporative cooling were studied. The incoming air had a dry-bulb temperature of 33 °C and a relative humidity of 28.4%. The study assessed the velocity, temperature, and relative humidity distribution in a cooling chamber. The optimum cooling system reduced the air temperature by up to 12℃ and increased relative humidity to 94% at 1.69 m/s inlet air velocity, 20 cm bundle thickness, and 30.23% porosity.