A semi-analytical lagrangian model to simulate the contaminants dispersion in the stable boundary-layer

A semi-analytical solution for the three-dimensional Langevin equation is presented and used to study the contaminant dispersion in the Stable Boundary-Layer (SBL). The method leads to a stochastic integral equation whose solution is based on the iterative solution of Langevin equation by the Picard’s Iterative Method. The novelty in this work relies on the consideration of the Eulerian autocorrelation function suggested by Frenkiel (1953) and Murgatroyd (1969). By this procedure the method is able to simulate the pollutant dispersion in the SBL for low wind and windy conditions, depending on the parameter associated with the characteristic period due the meander. The numerical simulations and comparisons with measured data performed shows a good agreement between predicted and observed values.