Abstract
A micro-scale model of air pollution dispersion generated by vehicles exhaust gas emission in the streets of Jakarta has been prepared and tested. This model is based on the assumption that the pollutants dispersion in the atmosphere is caused by gas diffusion to the vertical direction and convective effect of wind velocity and gas diffusion to the horizontal direction, which are orthogonal to the street. The exhaust gas emission from vehicles is assumed as infinite line source of pollutants. The variation of pollutants concentration with time is solved numerically by the alternating direct implicit method. The numerical results are compared to the measured pollutants concentration obtained by a sophisticated mobile unit.