Simulação numérica do transporte de um poluente inerte e passivo na CLP convectiva através de um modelo LES
DOI:
https://doi.org/10.5902/2179460X63623Keywords:
LES, Convective PBL, dispersion of inert pollutants. PBL numerical modelsAbstract
This work describes the time evolution of three dimensional structure of an inert and passive atmospheric pollutant, continuously emitted by an area source located at surface. These and other dynamic and thermodynamic properties of PBL are simulated numerically by the large eddy simulation model (LES) proposed by Moeng. The vertical structure of mean pollutant concentration and the associated vertical turbulent fluxes are consistent with a Mixed Layer, with approximately zero vertical gradients and vertical fluxes varying linearly with height. The vertical distribution of pollutant concentration variance does not follow the Mixed Layer Similarity Theory. The instantaneous vertical wind field shows an asymmetric spatial distribution, with skewness varying from 0.4, near the surface, to 1.62 at the PBL top. This result indicates that the updrafts are more intense and localized than the downdrafts. The spatial distribution of pollutant is consistent with the wind field pattern associated with the large eddies, mainly near to the top.Downloads
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