Abstract
This paper describes the numerical (CFD) analyses for thermal environment around the air-cooled outdoor units of air conditioning system installed on a roof of building to investigate the mechanism of Short-Circuit (SC) phenomenon. Especially, we focused on the effect of the condition of airflow around the air-cooled outdoor cooling units and the density of heat discharge. And then we developed the prediction formula to estimate the average or maximum rising inlet air temperature without CFD analyses and evaluated an effect of the decreasing inlet air temperature by applying various countermeasures. Based on these analyses, we proposed the method to estimate the required area for installing the air-cooled outdoor units and showed the possibility of decreasing the required area by applying various countermeasures.
