The spatial comfort and thermal delight of outdoor misting installations in hot and humid extreme environments

Abstract

Within the boundaries of Climate Change, existing hot and humid climates will likely become more extreme, calling for research into solutions that enable the thermal liveability of these environments. There is literature advocating for exploring evaporative cooling in hot and humid climates, having observed that when fine mist is deposited on skin, thermal comfort can be achieved. However, there are only a handful of studies considering the efficacy of misting prototypes in these environments. Thus, an experimental study was conducted to explore the impact of simple mist cooling technologies on outdoor comfort. A full-scale misting prototype was built in the city of Antofagasta, located in the Atacama desert region of Chile, and experiencing high humidity and massive solar radiation. The generated environmental conditions were measured, and thermal comfort questionnaires used to supplement quantitative data interpretation with information on the levels of comfort achieved.The experiment demonstrated the potential of mist cooling in this environment, which led to a significant reduction in air temperature, mean radiant temperature and thus on the universal thermal climate index, without significant increases in ambient humidity. Results showed over a 15 °C cooling effect in all three metrics at peak times, and occupants consistently reported a cooling effect after spending time within the mist.