Estudo comparativo entre coeficientes de difusão verticais na simulação da dispersão de poluentes em uma camada limite convectiva

Abstract

This work presents simulations for the pollutant dispersion in the Convective Boundary Layer (CBL) with a stationary three-dimensional semi-analytical solution, obtained by solving the advection-diffusion equation.The equation was solved by combining the techniques ADMM (Advection Diffusion Multilayer Method), based on the discretization of CLC in sublayers, each sublayer where the advection-diffusion equation is solved by the Laplace transform technique and GITT (Generalized Integral Transform Technique), a hybrid method that solves a broad class of direct and inverse problems. The new technique is then called GIADMT (Generalized Integral Advection Diffusion Multilayer Technique). The objective was to compare and analyze some of vertical diffusion coefficients, and their applicability in the three-dimensional concentration equation obtained by GIADMT method. Comparison entres appropriate to the atmosphere in unstable conditions vertical diffusion coefficients (Kz) was presented. The results were compared with experimental data of Copenhagen (Gryning and Lick, 1984; Gryning et al, 1987; Gryning and Lick, 2002) in order to verify the performance of the model under the various parameterizations of atmospheric turbulence. The comparisons showed better results when employing the parameterization suggested by Degrazia et al. (2001) [A].