Contribution to the Numerical Study and Parametric Analysis by CFD of Air Flows and the Distribution of Pollution in Old Neighborhoods of the Annaba Region

Abstract

Urban air pollution is a complex problem that requires a multidisciplinary approach to tackle effectively. Our study aims to understand how pollutants disperse in a built environment through airflow, which plays a crucial role in the transport, dispersion and concentration of pollutants. To demonstrate the impact of various factors such as urban configuration, buildings and urban voids that create turbulence and vortices affecting pollutant dispersion, we conducted a comparative study in two configurations, taking into account the city's meteorological conditions and pollution sources. The practical study involved simulating the dispersion of two pollutants-NOX emitted by road traffic, the main contributor in urban areas, and CO2, a greenhouse gas-in two existing urban fragments in the city of Annaba, using the Fluent code of the Eulerian CFD model for a more realistic analysis. The outcome of this quantitative and comparative study will focus on the effect of spatial configuration and morphology of buildings and airflow on air quality and pedestrian comfort. To reduce the impact of urban air pollution, it is therefore important to take these airflow phenomena into account in urban design (street layout, building height). Through numerical simulation of these complex processes, the effectiveness of various urban measures can be assessed.