A Numerical Model Studying the Unsteady - State Dispersion of Buoyant and Non - Buoyant Air Pollutants in the Atmosphere Under the Effects of Wet and Dry Deposition

摘要

The paper presents a two - dimensional dynamic mathematical model studying the unsteady - state dispersion of buoyant and non - buoyant air pollutants in the atmosphere under varying wind speed and eddy diffusivity. Realizing the importance of removal processes in alleviating the concentration of air pollutants from the atmosphere, the dry and wet deposition of pollutants have been considered in the model. The numerical solutions to the developed advection - diffusion model are obtained through fractional step method. Lagrangian technique is used for the advection step and finite element method of weighted - residual is applied for solving the diffusion step. The solutions are examined through concentration profiles and these obtained profiles throw light onto the importance of mitigation strategies in dealing with an increasing level of pollutants below the source Height, especially near the ground.