NUMERICAL AND EXPERIMENTAL INVESTIGATION OF THE PERFORMANCE OF AN EVAPORATIVELY-COOLED CONDENSER

Abstract

The coefficient of performance (COP) of air-conditioning systems is inversely proportional to the temperature lift between evaporator and condenser. For the reduction of this temperature lift, faster heat rejection methods need to be explored. Evaporative cooling of the air-cooled condensers with water spray is identified as one of the techniques for this category of condensers. A detailed theoretical model was developed to study the heat and mass transfer characteristics of unfinned (bare) and finned evaporatively-cooled condensers of air-conditioners under different operating conditions. A 5.8 kW capacity split air-conditioner was modified to incorporate the evaporative cooling and experiments were performed. The detailed theoretical model has been validated using the experimental results. A simplified model was also developed and its numerical results compared with the detailed model and experimental results. A brief analysis on the benefits and potential challenges in the implementation of evaporatively-cooled condensers in the Singapore context has also been performed.