Plume Dispersion Characteristics in Various Ambient Air Temperature Gradient Conditions

Abstract

The dispersion of plume which is emitted from a chimney is governed by many of factors: wind speed, wind direction, local terrain, turbulence intensity of atmosphere, temperature, etc. In this study, we numerically investigate the plume dispersions for various altitudinal temperature variations. The normal atmosphere has a temperature decrease of −0.6°C/100 m, however, the real atmosphere has various altitudinal temperature profiles (−1.5 ∼ 1.0°C/100 m) according to meteorological factors. Air can occasionally make very strong upward/downward wind current or flow fluctuation due to buoyancy force. In this study, the results of the plume dispersion are introduced along the altitudinal temperature variation. The developing processes of the plume after being discharged from a stack and the ground level concentrations at various positions, are compared under various altitudinal temperature conditions.