Keywords: atmospheric dispersion modelling, convective boundary layer, complicated terrain, Lagrangian stochastic model, potential flow model, air pollution, air quality, regulatory use, simulation, atmospheric stability, unstable conditions
Development of numerical model for dispersion over complicated terrain in the convective boundary layer
Complicated terrain and atmospheric stability are important factors in the predicting the dispersion of air pollutants. The aim of our study is to develop practical dispersion model for unstable conditions for regulatory use. The numerical model we adopted was a combination of the potential flow model and Lagrangian stochastic dispersion model. In this model, time-mean flow field is solved by the potential flow model and concentration field is calculated by Lagrangian stochastic model by using the flow field from potential model. Wind tunnel experiments simulating gas dispersion in the convective boundary layer were also done. The data sets of turbulent properties and concentrations obtained in the wind tunnel were used for the modification of dispersion model and model validation. Based on the developed model, user-friendly software applicable to dispersion over complicated terrain was also developed.