CFD Analysis of Urban Airflow and Particulate Dispersion in a Mining-Influenced Neighborhood Using Real Topography Data

Resumo

Urban areas located near ore management or mining sites may be affected by air pollution caused by the emission of particulate matter resulting from activities associated with the mineral production chain. Besides the deposition of dust in roads, plants and houses everywhere along the wind stream, suspended particulate matter has negative effects on the population’s health, from aggravating to being the cause of cardiovascular and respiratory diseases. Accordingly, the present study aims to evaluate the airflow through the streets and between residential blocks located in a neighborhood within the urban area of the municipality of Congonhas, in the state of Minas Gerais, situated near mining activities, using computational fluid dynamics (CFD). For this purpose, the software Ansys Fluent was employed to carry out the computational simulations, in which the actual topography of the terrain related to the studied case was considered. Recent works in particulate matter carried by wind uses simplified geometry of the terrain to model the basis of the air flow in urban regions. In contrast, the present analysis uses the official terrain scan made available by the city hall which excludes buildings and vegetation, but considers the detailed topography. Also, the input data of wind velocity profile is from a mining site, to better suit the local context and use an already fully developed airflow. Based on the analysis of different wind directions, it is possible to identify areas with low and high wind velocities, in which occurs deposition and emission of particulate matter. Furthermore, the integrated use of these tools and datasets enables a quantitative assessment of the performance of existing strategies in controlling particulate matter emissions. Moreover, the methodology supports the identification of optimal technologies and spatial deployment strategies for future interventions aimed at achieving effective dust pollution reduction.