The increasing temperatures in cities call for solutions to reduce the exposure to high thermal stress. Water misting is an effective, controllable, and resource-friendly technology for local cooling, yet a limited number of operating setups are explored in literature. In this study, an urban cooling shelter fitted with a misting system is experimentally tested in combination with i) top solar shading, ii) side wind shielding, and/or iii) smart controller. Tests were performed in the northern outskirts of Rome between June and August 2021. The study showed that the median air temperature reduction between the misted zone and the undisturbed observation point was close to 3.5 °C in the reference scenario (misting + solar shading). The comfort-driven smart control realised a similar cooling profile with significantly attenuated humidification, narrower variability, and drastically reduced resource consumption (80 % reduction in pump activation). As the cross-ventilation was blocked along the longitudinal axis through the installation of a wind shield, the cooling rose dramatically, hitting a median of −7.5 °C and a maximum close to 10 °C, with strong local humidification and pronounced thermal gradients. It was further observed that the way environmental conditions outside the misted perimeter dictate the evaporative cooling potential varies for different configurational and operating settings.
Experimental assessment of the heat mitigation potential of an urban cooling shelter: Combining water misting with solar shading, wind shield, and smart control
Zinzi M.
2023-01-01
Abstract
The increasing temperatures in cities call for solutions to reduce the exposure to high thermal stress. Water misting is an effective, controllable, and resource-friendly technology for local cooling, yet a limited number of operating setups are explored in literature. In this study, an urban cooling shelter fitted with a misting system is experimentally tested in combination with i) top solar shading, ii) side wind shielding, and/or iii) smart controller. Tests were performed in the northern outskirts of Rome between June and August 2021. The study showed that the median air temperature reduction between the misted zone and the undisturbed observation point was close to 3.5 °C in the reference scenario (misting + solar shading). The comfort-driven smart control realised a similar cooling profile with significantly attenuated humidification, narrower variability, and drastically reduced resource consumption (80 % reduction in pump activation). As the cross-ventilation was blocked along the longitudinal axis through the installation of a wind shield, the cooling rose dramatically, hitting a median of −7.5 °C and a maximum close to 10 °C, with strong local humidification and pronounced thermal gradients. It was further observed that the way environmental conditions outside the misted perimeter dictate the evaporative cooling potential varies for different configurational and operating settings.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
