Keywords: particle concentration, simulation, street canyons, traffic emissions, emission source, vehicle emissions, buildings, street geometry, PM10, particulate matter, FLUENT software, air quality, air pollution, atmospheric dispersion modelling, Portugal, air flow, turbulence, computational fluid dynamics, CFD, wind speed
Studying street geometry influence in PM10 concentration
This paper intends to show the influence of street geometry in particle concentration emitted from traffic source, on a busy street of Barreiro City, Portugal. FLUENT software was used to simulate particle dispersion, air flow and turbulence in the street. Buildings and road characteristics were considered, as well as winter and summer most predominant meteorological conditions. Also, particle concentrations were measured. The results show that when street orientation is equal to wind orientation, a good dispersion is promoted and low particle concentrations are achieved. Concerning the effect of building height, some recirculation is noticed affecting mainly the residents. In this street geometry north wind direction promotes some positive recirculation raising wind velocity and pollutant dispersion, while the effect of south winds is negative since the wind speed is lower, trapping particles. Considering some differences in the geometries it was possible to conclude that some gaps between buildings could help pollutants' dispersion.