Thermal Effects on Pollutant Dispersion in a Street Canyon

A calculation method combining a simple energy balance model and CFD simulation is proposed in this paper to study the thermal effects on pollutant dispersion in real street canyons. The surface temperature calculated by the independent energy balance model can be used as thermal boundary by CFD simulation. Using the combination calculation method, the wind flow and pollutant transport inside an idealized street canyon is studied. The simulation results show that only slight influence of buoyancy effects on the flow structure in the street canyon, even at small Froude number. However, the thermal effect can significantly affect the pollutant distribution and air exchange between the street canyon and the above roof flow.