Observing Temperature Changes and Wind Speed Variations in an Urban Canyon of Shiraz at Different Heights Using CFD Simulation

Shoara, Shoeleh; Mofidi Shemirani, Seyed Majid; Shahriari, Seyed Kamaleddin; Zarabadi, Zahra Sadat Saeideh

doi:10.22034/ijumes.2024.2023472.1196

Observing Temperature Changes and Wind Speed Variations in an Urban Canyon of Shiraz at Different Heights Using CFD Simulation

Document Type : Case Study

Authors

Shoeleh Shoara ¹

Seyed Majid Mofidi Shemirani ²

Seyed Kamaleddin Shahriari ³

Zahra Sadat Saeideh Zarabadi ⁴

¹ Ph.D. Candidate, Department of Civil engineering, Faculty of Art and Architecture, Science and Research Branch, Islamic Azad University, Tehran, Iran

² Associate Professor, Department of Urban Design, Faculty of Art and Architecture, Iran University of Science and Technology, Tehran, Iran

³ Assistant Professor, Department of Civil engineering, Faculty of Art and Architecture, Science and Research Branch, Islamic Azad University, Tehran, Iran

⁴ Associate professor, Department of Urban Planning, Faculty of Art and Architecture, Art and Architecture, Science and Research Branch, Islamic Azad University, Tehran, Iran.

10.22034/ijumes.2024.2023472.1196

Abstract

The utilization of natural ventilation in urban canyon plays a substantial role in lessening energy consumption and heat island effects. Therefore, the determination of suitable street canyon form is very influential. Due to rapid urbanization, industrial activities and massive construction in Shiraz during the recent years, it is inevitable to investigate the new development effects. The aim of this study is to investigate how strategic urban design can influence natural urban ventilation through the analysis of wind flow simulations, with the goal of informing urban planning. This study aims to numerically simulate air flow, heat transfer and solar radiation over a large-scale buildings at different altitudes in Hosseini Al-Hashemi Expressway, Shiraz, Iran by using Ansys Fluent. According to the solution method of this research, after obtaining the initial solution using the k-ε model, the problem was switched to the LES method, and the final solution was solved by this method. In addition, convective, conductive, and radiation flows were calculated through the governing equations of fluid dynamics using Monte Carlo model. The results show that the blocked flow at 2 m height was released at 25 m height due to a larger eddy. It can be concluded that the design of the urban canyon located next to the busy highway, effectively repels heat and has good ventilation.

Keywords

Air temperature

Ansys Fluent

Heat Island Effects

natural ventilation

urban canyon

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