Study on Air Cooling Using Chemical Reaction Heat and Sensible Heat on Evaporation

Abstract

To develop for a simple and portable air cooling system, this study investigated a method that utilizes both the cold heat generated when urea is dissolved in water and the latent heat of evaporation absorbed during the evaporation of water in aqueous solution. In the basic experiments, air was blown into water and aqueous urea solution, and fillings were placed in the vessel to promote gas-liquid contact. As a result, the liquid temperature was effectively cooled. A numerical model based on the heat and mass balances were developed to investigate the air blowing process. The depression of vapor pressure due to the addition of urea was considered in the calculation. The present model reasonably predicted the tendency of the easured liquid temperatures especially for using fillings in the experiment. The cooling system is numerically investigated and showed that the effect of urea concentration on cooling by evaporative latent heat was small under low humidity conditions.