A Numerical Simulation of Fog Dissipation Using Passive Burner Lines. Part II: Sensitivity Experiments

Abstract

A two-dimensional model (Tag, 1979) is used to perform sensitivity experiments simulating fog dissipation using passive burner lines under both cross-wind and no-wind conditions. For a cross-wind experiment, heat output and cross-wind speed are found to be the two overriding factors which control the height of a clearing. It is determined that the extent of the fog clearing is inversely linked to the fog liquid water content, and that the fog thermal structure as well as the moisture emitted by the hydrocarbon combustion in the line have minimal effect on the size of the resulting clearing. Under no-wind conditions, where two lines of equal heat output are positioned on either side of a runway, heat output and line separation are the key controls to a surface clearing. Depending on the strength of the line heat release, either a downdraft or updraft can form between the lines, with the latter producing the quicker surface clearing. The no-wind experiments suggest that the use of a blower system in conjunction with two burner lines would be more efficient than relying on heat-induced circulations alone.