International Journal of Architectural Engineering & Urban Planning

en A Numerical Study of Airflow and Average Temperature in Different Canyon Aspect Ratios: Case Study of Shiraz Urban Design Urban Design Research Paper Research Paper The utilization of natural ventilation in urban canyons plays a substantial role in lessening energy consumption and heat island effects. Determining the appropriate street canyon form is then very influential. In this study, Ansys Fluent was used to numerically measure airflow, heat transfer, and solar radiation in five three-dimensional urban environments with aspect ratios (3, 2, 1, 2/3, 1/3). The 𝑘−𝜀 turbulence model was used for the initial modeling and large eddy simulation of the final one. Three types of materials (gray aluminum composite, gray concrete, and white stone chipping) were considered for buildings and asphalt as ground material. The results showed that increasing the building surface fraction increased the walls’ average temperature and decreased the walls’ net longwave flux for three material types. Moreover, the aspect ratio was directly related to the average wall temperature and inversely related to the net long-wave flux of walls. Furthermore, the results showed that eddy height tracked the street canyon height at different aspect ratios. Comparisons also revealed that the magnitude of the vortices generated next to the buildings is approximately the same for the three materials Local Climatic Zone, Urban Canyon Form, Large Eddy Simulation, Surface Material 0 0 http://ijaup.iust.ac.ir/browse.php?a_code=A-11-57-1&slc_lang=en&sid=1 Shoeleh Shoara sshoaraa@yahoo.com 180031947532846008289 180031947532846008289 No Faculty of Civil engineering, Art and Architecture, Science and Research Branch, 6 Islamic Azad University, Tehran, Iran Seyed Majid Mofidi Shemirani s_m_mofidi@iust.ac.ir 180031947532846008290 180031947532846008290 Yes School of Architecture, University of Science and Technology, Tehran, Iran Seyed Kamaleddin Shahriari shahriari@srbiau.ac.ir 180031947532846008291 180031947532846008291 No Faculty of Civil engineering, Art and Architecture, Science and Research Branch, 16 Islamic Azad University, Tehran, Iran Zahra Sadat Saeideh Zarabadi z.zarabadi@srbiau.ac.ir 180031947532846008292 180031947532846008292 No Faculty of Civil engineering, Art and Architecture, Science and Research Branch, Islamic Azad University, Tehran, Iran.