Comparison of the Influence of Coniferous and Deciduous Trees on Dust Concentration Emitted from Low-Lying Highway by CFD

Abstract

Different types of vegetation barriers are frequently used for reduction of dust and noise levels. The effectivity of the measures depending on the type of used vegetation (decideous, coniferous) is studied in this article. The mathematical model is based on Reynolds—averaged Navier–Stokes (RANS) equations for turbulent fluid flow in Boussinesq approximation completed by the standard k model. Pollutants, considered as passive scalar, were modelled by additional transport equation. An advanced vegetation model was used. The numerical method is based on finite volume formulation. Two fractions of pollutants, PM10 and PM75, emitted from a four–lane highway were numerically simulated. Forty-nine cases of coniferous and deciduous-type forest differing in density, width and height were studied. The main processes that play a role in modelled cases are described. The differences between the effects of coniferous and deciduous trees on pollutants deposition were studied.