Keywords

Street canyon, Urban vegetation, Dry deposition, RANS modelling, Moment method

Location

Session A1: Environmental Fluid Mechanics - Theoretical, Modelling and Experimental Approaches

Start Date

12-7-2016 11:30 AM

End Date

12-7-2016 11:50 AM

Abstract

In this paper we investigate the effects of the vegetation inside a street canyon. Flow through and around the standalone street canyon is calculated using a CFD solver based on the Reynoldsaveraged Navier-Stokes equations. The dispersion of the pollutant is computed using the moment method that models the behaviour of the particle size distribution. Resulting pollutant concentrations for several wind conditions and for configurations without and with the trees are compared to the wind tunnel measurements. Using the deposition velocity model for the moment method, the effect of the dry deposition on the vegetation is then assessed. Three modes of the particle size distribution - the ultrafine, the accumulation, and the coarse mode - are studied. Results show that the the dry deposition has negligible effects on the accumulation and the ultrafine mode, but can locally reduce the mass concentration of the particles in the coarse mode by more than 10%.

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Jul 12th, 11:30 AM Jul 12th, 11:50 AM

Investigating the Street Canyon Vegetation Effects Using the Moment Method

Session A1: Environmental Fluid Mechanics - Theoretical, Modelling and Experimental Approaches

In this paper we investigate the effects of the vegetation inside a street canyon. Flow through and around the standalone street canyon is calculated using a CFD solver based on the Reynoldsaveraged Navier-Stokes equations. The dispersion of the pollutant is computed using the moment method that models the behaviour of the particle size distribution. Resulting pollutant concentrations for several wind conditions and for configurations without and with the trees are compared to the wind tunnel measurements. Using the deposition velocity model for the moment method, the effect of the dry deposition on the vegetation is then assessed. Three modes of the particle size distribution - the ultrafine, the accumulation, and the coarse mode - are studied. Results show that the the dry deposition has negligible effects on the accumulation and the ultrafine mode, but can locally reduce the mass concentration of the particles in the coarse mode by more than 10%.