Presentation on theme: "NATO ASI Conference, Kyiv-20041 Pollutant Dispersion Investigation of buoyancy effects on distribution of mean concentration field in the turbulent circulation."— Presentation transcript:
NATO ASI Conference, Kyiv-20041 Pollutant Dispersion Investigation of buoyancy effects on distribution of mean concentration field in the turbulent circulation flow above an urban heat island was the main goal in modeling and simulation of pollutant dispersion from a continuous surface source.
NATO ASI Conference, Kyiv-20042 Pollutant Dispersion Experimental measurements were not available for the quantitative validation of simulation data. Instead, we present some preliminary results that illustrate interesting properties of pollutant dispersion from a continuous source located inside the urban heat island.
NATO ASI Conference, Kyiv-20043 Vector field of turbulent concentration fluxes above an urban heat island
NATO ASI Conference, Kyiv-20044 Pollutant Dispersion Thus,one characteristic feature is observed in the pollutant dispersion. The contaminant penetrates not only into the inversion layer but even higher beyond its boundary. This behavior was recently reproduced in the laboratory experiments of Snyder et al. (BLM,2002, vol.102, 335-413.). These experimental data clearly show penetration of the continuous buoyant plumes into the inversion and above the convective boundary layer.
NATO ASI Conference, Kyiv-20045 Calculated of concentration contours above an urban heat island C a l c u l a t i o n: ---- algebraic mass fluxes model transport equations fluxes model The maximum difference of concentration level near to a source does not exceed five percents. The executed verification specifies validity of use of the algebraic turbulent mass fluxes model in practice of modeling and simulation of atmospheric contaminant dispersion.
NATO ASI Conference, Kyiv-20046 CONCLUSION The four-equation model for the description of pollutant dispersion in the stable stratified atmospheric boundary layer is formulated. Favorable comparison the numerical results of pollution dispersion from the continuous surface source above the urban heat island with laboratory measurements is found.