Showing 2 results for Building Height
Hadi Rezaei Rad, Zahra Khodaei, Mohammad Mehdi Ghiai,
Volume 33, Issue 4 (12-2023)
Abstract
Urban planning and morphology are one of the most important factors affecting land surface temperature (LST) and microclimate chrematistics. The production of anthropogenic heat, mainly for cooling systems and lighting, has resulted in significant impacts on the quality of the thermal environment. These impacts include poor air quality, increased temperatures, higher energy consumption, and the development of urban heat islands (UHIs). With the growing urban population and increased building height, especially in metropolitan areas, there have been significant changes in the urban geometry, rate of pollution, amount of heat released, and meteorological parameters. All these factors contribute to the heat island phenomenon and significantly alter the microclimate in urban areas. The goal of this article is measuring the effects of height changes in buildings around Tehran metropolitan squares in a detailed plan on microclimatic changes. As part of a research study, the Hafthoz Square in Tehran was chosen as a case study. The researchers used a combination of simulation techniques (Envi-met) and GIS to detect the spatial variation of Land Surface Temperature (LST) and determine its quantitative relationship with building height and density. This was achieved through simulation modeling for the Narmak neighborhood of Tehran. As Conclusion, the results indicate that comparison on the simulation between the existing conditions and proposed scenario area showed that in the proposed scenario, wind speed and relative humidity decrease and ground surface temperature (UHI) and PPD and PMV indices increase. Therefore, if the detailed plan of Tehran metropolis is realized and implemented in many squares, it will be accompanied by changes in micro-climatic parameters in order to reduce the thermal comfort of citizens.
Mehrdad Karimimoshaver, Shima Nouri, Banu Özkazanç,
Volume 34, Issue 4 (10-2024)
Abstract
Air pollution in many cities is influenced by wind speed and direction, which in turn are affected by urban morphology.
Air quality is closely related to urban fabric, which refers to the physical layout and design of urban areas. Factors such as building density, green spaces, transportation infrastructure, land use, and the shape and size of buildings significantly influence air quality. These features affect the concentration of pollutants in the environment by shaping wind flow and local dispersion patterns. This study examines how the height of buildings influences air pollution. In recent years, the strong tendency towards the construction of tall buildings has had adverse effects on cities. The rise in tall buildings, along with their impact on wind flows and the spread of pollutants, presents a significant challenge for urban planners. Today, the risks of air pollution are increasing, and therefore methods of monitoring how pollutants are released are of particular importance. This study evaluates the impact of tall buildings on pollutant dispersion and aims to provide a program tailored to the data obtained to control and improve the current situation. This research was conducted on two groups of buildings in the southwestern part of Tehran (District 18) using computational fluid dynamics (CFD) simulation and geographic information systems (GIS). The results of the study show that as the wind speed in a path increases, the concentration of pollutants decreases. Additionally, increasing the height of a building in a single state increases the wind speed on two sides and decreases the wind speed on the other two sides. In general, based on the assumption of pollutant dilution with increasing wind speed, building height plays an effective role in pollution dispersion.
