Abstract
Non-atomizing misting systems have typically been employed to alleviate the problem of thermal heat stress among occupants and have been shown to be effective especially in temperate countries. However, its impact in tropical countries is not widely studied and it is the same for the impact of the water temperature on reducing air and skin temperature. Using CFD simulation models, this paper seeks to address these gaps. A Langrangian-Eulerian approach is adopted using the Steady K-Epsilon turbulence model and Discrete Phase Model in Ansys Fluent software. Inputs for misting spray and modelling human skin are adopted from other published papers, and Grid Independence studies are also conducted. The results show that Misting sprays can cool the air temperature by up to 4.5 degrees C, based on a hot afternoon condition in Singapore and there is an almost linear relationship between water temperature and cooling effect. At 3m downstream from nozzle, a 45 degrees C water temperature leads to neither decrease nor increase in air temperature. Skin temperatures can also be reduced by a maximum of 3 degrees C. Due to thermal properties of water, even 95 degrees C water temperature only increases air temperature by less than 4 degrees C.