Heat stress mitigation in urban streets having hot humid climatic conditions: Strategies and performance results from a real scale retrofitting project. (3rd May 2022)

• Record Type: Journal Article
• Authors: Zeeshan, Muhammad; Ali, Zaib
• Is Part Of: Science and technology for the built environment. Volume 28:Number 4(2022)
• Page Start: 513
• Page End: 526
• Publication Date: 2022-05-03
• Subjects: Heating -- Periodicals; Ventilation -- Periodicals; Air conditioning -- Periodicals; Refrigeration and refrigerating machinery -- Periodicals; Indoor air quality -- Periodicals; Indoor air quality; Air conditioning; Heating; Refrigeration and refrigerating machinery; Ventilation; Periodicals; 697
• DOI: 10.1080/23744731.2022.2040322
• Languages: English
• ISSNs: 2374-474X

Abstract

Abstract : The urban heat island (UHI) phenomenon has become a major concern for city sustainability in the wake of global warming and rapid urbanization. This has resulted in increased heat stress and worsened outdoor thermal comfort in urban microclimates. The study demonstrated that outdoor thermal stress pedestrians can be reduced in single streets by adopting mitigation strategies, that is, cool materials, vegetation, and water bodies. In this article, computational fluid dynamics (CFD) simulations using URANS modeling for four different scenarios have been performed to investigate the effectiveness of different mitigation measures in hot, humid urban climates conditions. The reduction of ambient air temperature and surface temperature characterizing the mitigation (cooling) intensity is examined at pedestrian height and diverse vertical levels. The analysis shows that on its own, water provides the largest reduction in air temperature at pedestrian height (2 °C), and cool materials provide a larger reduction in surface temperature (6 °C). When applied individually, cool materials are the more effective in the vertical direction with a UHI mitigation intensity of 1.5 °C, followed by vegetation, with a mitigation intensity of 1.0 °C. Furthermore, the impact (temperature reduction) is more significant when all three measures are combined, with a large reduction of 2 °C in air temperature and 9 °C in surface temperature observed compared to the reference case.