Review and validation of MicroSpray, a lagrangian particle model of turbulent dispersion

In this paper, the MicroSpray 3-D Lagrangian particle dispersion model is presented and reviewed, and several validation studies are shown. Starting from its core, based on a 3-D form of the Langevin equation for the random velocity, the successive developments of different modules treating the main physical processes that determine the atmospheric pollutant dispersion are illustrated. Different probability density functions are implemented to estimate the deterministic coefficient in the Langevin equation. Buoyancy effects are described through simplified plume rise formulations up to a complete set of equations for negatively and positively buoyant emissions, also including phase changes. MicroSpray is able to simulate different types of sources and emissions; it includes the treatment of obstacles and complex orography and offers several options to optimize the numerical runs. The model can be driven both by diagnostic and prognostic atmospheric models, and it has been used and validated in a variety of cases, from experimental to real conditions. Some significant examples of MicroSpray simulations are detailed and discussed. © 2012. American Geophysical Union. All Rights Reserved.