Predictions of Air Pollution from an Offshore Airport

Part 1. Evaluation of Dispersion Model with the Tracer Experiments

Abstract

In this paper, the atmospheric dispersion model of emissions from an offshore airport is discussed and the calculated results are compared with those obtained from the tracer dispersion experiments.
The model proposed in this study is a combined one, puff and plume model. The dispersion of aircraft emissions is simulated by puff model and emissions from non-aircraft airport activity is plume model.
Exhaust gas of operating aircraft is replaced by the series of puffs which are released from the sources located along the path of aircraft with constant interval. The strength of a puff is determined by the emission rate of engine and interval length of sources. Puffs are flowed by wind and diffused by atmospheric turbulence. The concentration of pollutant gas at a receptor point is obtained from the integration of concentrations owing to all puffs affected to this point.
The accuracy of puff model is evaluated using the results of tracer experiments carried out at the proposed sites of Sin Kansai International Airport. From the comparisons of calculated and observed results, it is cleared that the choice of diffusion factors is very important to get a good agreement and the model is valid not only for steady meteorological condition, but also unsteady condition, such as the interaction of sea and land breezes.