Emission spread from mass and energy exchange in the atmospheric surface layer: Two-dimensional simulation

Abstract

This article provides an original method for simulating the spread of hazardous emissions in the atmospheric surface layer in the event of emergencies The modeling process implies the development of a mathematical tool based on the partial differential equation (PDE) of turbulent diffusion. It is also based on a steady-state equation for determining the contaminant dispersion during an emergency with regard to the elapsed dispersion time, volumetric nature of the contamination source, wind speed. The model allows studying the changes in air composition that have occurred under various meteorological (wind speed and direction, temperature, fogs, precipitation, dust winds) and anthropogenous factors. An attempt was made to calculate the probable contamination area around the arbitrary system of sources with high contaminant concentration under unfavorable weather conditions. The original method for calculating the movement and dispersion of emissions allows forecasting the contaminant concentration level in the two-meter layer above the ground and the vertical concentration distribution with regard to the landscape, identified according to the meteorological data. Our model can be easily scaled on any territory; the entire line of complex landscape features was taken into account by introducing a model of weather statistics for the research region.