INFLUENCE OF STREET CANYON GEOMETRY ON WIND FLOW PATTERNS AND FIRE PLUME DISPERSION: A NUMERICAL STUDY

Darko Zigar, Dušica Pešić, Aca Božilov

DOI Number
https://doi.org/10.22190/FUWLEP250225002Z
First page
015
Last page
024

Abstract


Computational Fluid Dynamics techniques are widely applied to predict pollutant transport within urban areas. In this study, the Large Eddy Simulation (LES) method of the Fire Dynamic Simulator (FDS) software package has been used to investigate the effects of building geometries on fire plume dispersion generated by a car fire and atmospheric pollution under wind conditions. The simulations have been carried out for four separate cases of different street canyon configurations (one case of uniform canyons and three cases of non-uniform canyons as the combinations of step-up and step-down notches), commonly found in many urban areas. The results show that the street geometry is crucial for airflow and pollutant dispersion inside and over the canyons. Due to different building heights, there is a strong interaction between the wind flow at the street rooftops and the in-canyon fire plume flow. The flow field patterns in the canyons are changed depending on the building geometries. These geometries also affect the wind inflow into canyons, and consequently, the generation, transport and dispersion of fire pollutants. The results of this study show that the air pollution level in complex structures can be effectively investigated by using the FDS LES model. Moreover, these results can be used not only to assess the air pollution level under extreme conditions such as fire accidents, but also to support urban planning and air quality control strategies aimed at reducing air pollution levels in urban areas.

Keywords

Large eddy simulation, Street canyon geometry, Fire accident, Wind flow, Air pollution

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References


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DOI: https://doi.org/10.22190/FUWLEP250225002Z

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