DEVELOPMENT OF OVERLAPPING MODELING FOR ATMOSPHERIC DIFFUSION

Diffusion modelling in wind tunnels is well-known as a very useful technique to predict pollutant gas concentrations released from continuous sources in complex terrain for environmental assessment. The similarity laws for atmospheric diffusion modelling entail simulation of turbulent fluctuations of wind direction sigma(A), observed over the concentration averaging time, in the wind tunnel. The new concentration overlapping system with the turntable of 12 m diameter in the wind-tunnel lest section has been developed and shown to be useful to simulate longer, hourly averaged concentration and to predict the TAF (terrain amplification factor) and the TAP (terrain affected peak) in complex terrain.