Computational fluid dynamics simulation of fog clouds due to ambient air vaporizers

Ambient air vaporizers (AAVs) are widely used to regasify liquefied industrial gases, which are liquefied for transport and storage. Depending on the conditions (temperature and relative humidity) of ambient air and AAV effluent, the potential exists for the formation of fog as the two fluids mix with each other. This has raised some regulatory and environmental concerns that the fog cloud may impact human activities in the vicinity of the AAV arrays.This paper describes a CFD-based modeling approach to predict the formation, dispersion and dissipation of a fog cloud due to AAV operation. The model uses the psychrometrics equations to determine when saturated air conditions are reached and to calculate mass and energy transfer between the moist air and the fog cloud. A parametric study is presented, based on an array of 6 AAVs, to demonstrate the effects of wind speed and AAV discharge elevation on the behavior of the fog cloud.