A lattice gas model with temperature and buoyancy effects to predict the concentration of pollutant gas released by power plants and traffic sources

摘要

A method to simulate the dispersion of pollutant gases in the air, which is based on the lattice gas technique, is presented. The model is able to represent the main transient and local effects, thus it is an alternative to the direct numerical simulation of the turbulent diffusion paths. No parametrization of the turbulence is needed, nor of the momentum and energy exchange between the pollutant and the air. Few non-dimensional parameters define completely the case to study. The predictions of the model, including the buoyancy effects, are compared in the steady-state limit with the Gaussian plume equation. The effective values of the dispersion coefficients and of the plume rise height are extracted from the results and are compared with the values resulting from the application of the most widely used semi-empirical correlations.