Estudo numérico da dispersão de poluente veicular em uma microrregião urbana

Abstract

Industrialization and the exponential population growth are daily accompanied by significant impacts on the environment, well-being and human health. Acting as major contributors, pollutants emitted by motor vehicles are present in the atmosphere, dispersing and acting as invisible villains. In this context, the study of air pollutants dispersion helps to create solutions that can improve the population’ life quality. In Brazil, there are still few researches related to the subject, and air quality monitoring data are not frequently obtained. Aiming to broaden the understanding of atmospheric pollutants dispersion at Ponta Grossa, city that occupies 5th place in car numbers at Paraná state, this research presents itself as a pioneer in the study of carbon monoxide (CO) at an urban micro region downtown. Also contemplating a projection of future scenario considering the exchange of current buses fleet to electric ones. At the simulated site there is a large circulation of pedestrians and an air quality monitoring station. The CO mass flow in the simulated routes was calculated based on literature emission factors and the manual counting of the vehicles flow in the site. The simulations were performed using a computational fluid dynamics (CFD) tool, commercial software ANSYS/FluentTM19.1. With the results, it was possible to obtain visualizations of the fluid dynamics conditions in the place, demonstrating possible pollutants accumulations due to recirculation region and wind characteristics. The results of CO concentration are around 15 ppm, considering 1.5 m of heightin relation to the ground level, above 9 ppm, considered the limit according to the national air quality standards. In the future scenario projection, with the change of all conventional buses that circulate in the place to electric buses, a reduction of up to 8.5% in CO emissions was obtained, which reflects in the improvement of the air quality to the local population.