Analysis of the system response of a spray passive downdraft evaporative cooling system.

A spray Passive Downdraft Evaporative Cooling (PDEC) system achieves great savings for space cooling and improves indoor environmental quality by supplying a large amount of fresh outdoor air. As previous studies heavily focused on the energy saving capability of a spray PDEC system due to lack of methods for a detailed analysis, the influence of cool humid supply air from a spray PDEC system in a space in buildings has not been comprehensively studied. This study is intended to evaluate the competence of a spray PDEC system as a primary cooling system in typical spaces in a primary school building by developing a method using building energy simulation tool. It runs one-day simulations in a hot dry climate and a warm moderate climate in order to distinctly examine the benefits and the areas that should be advanced. It analyses how a spray PDEC system responds to the space cooling loads and spaces conditioned by the system thermally behave. The results of the simulations affirm that a spray PDEC system is capable of conditioning building spaces in the two climates, indicating some areas to be improved. • The study develops the most accurate method to examine the impact of the system. • A water flow rate of 150l/h or greater is reasonable. • A constant supply air temperature is essential to mitigate adverse effects. • The system may be more effective to serve small building spaces. • The results suggest a finer control to maximize energy efficiency of the system. [ABSTRACT FROM AUTHOR]