Investigation of the influence of jet supply configurations on the thermal and flow behaviors of the wall-attached night ventilation system. (August 2022)

• Record Type: Journal Article
• Authors: Li, Yajun; Ji, Wenhui; Jiang, Fujian; Yu, Tao; Zhou, Jinzhi
• Is Part Of: Sustainable cities and society. Volume 83(2022)
• Publication Date: 2022-08
• Subjects: Night ventilation -- Wall-attached ventilation -- Parametrical study -- Turbulence model -- Supply air conditions; Sustainable urban development -- Periodicals; Sustainable buildings -- Periodicals; Urban ecology (Sociology) -- Periodicals; 307.76
• DOI: 10.1016/j.scs.2022.103957
• Languages: English
• ISSNs: 2210-6707

Abstract

Highlights: The influence of jet supply configurations on the WANV system is studied. The dimensionless maximum velocity decay is established. The optimized supply air velocity is 4 m/s. The critical dimensionless distance s/b is 10. The optimal installation angle for a large slot inlet distance is specified. Abstract: Facing the goal of carbon abatement to energy conservation and emission reduction, night ventilation has attracted increasing attention from scholars. As the night cooling performance is greatly influenced by the climate conditions, the wall-mounted attached night ventilation (WANV) has been proposed to achieve enhanced convective cooling performance for the region with a small diurnal temperature range. The present paper aims at investigating the airflow patterns and temperature field under different jet supply configurations. A numerical model is built and validated and further employed to evaluate the effect of supply air velocity, slot inlet location, and slot inlet angle. The dimensionless maximum velocity decay under different supply air velocities is established, while a slow jet velocity decay is found due to the buoyancy force driven by the heated wall. In addition, the thermal evaluation indicates that the supply air velocity of 4 m/s shows the best cooling performance. Considering the practical situation, the impact of the slot inlet orientation is further investigated. The results show that the critical dimensionless distance of the slot inlet to the adjacent wall s/b is 10 when the supply air velocity is 4 m/s, and the optimal installation angle for a large slot inlet distance is specified.