Numerical simulation of the dispersion of vehicular exhausted gaseous pollutants discharged from the tunnel ventilation tower

The numerical simulation model of the dispersion of gaseous pollutants and the atmospheric turbulence around the wind tower was presented.A wind tunnel test of the modeled tower was carried out based on the similarity theory.The experimental results show a good agreement with the numerical simulation.According to the meteorological characteristics of Shanghai,the underlying surface parameters,wind profile and turbulent diffusivity were determined.The dispersion of CO and NOx exhausted from the wind tower of Dapu Road underground tunnel was simulated under the different characteristics of typical wind speed and directions.The features of dispersion distance and influence range are revealed.The retardation of buildings around the tower reflects the typical characteristics of diffusion.The simulation results can be used as a reference for ventilation tower designing.