FRONTIERS IN MARINE SCIENCE, cilt.7, no.600614, ss.1-11, 2020 (SCI Expanded İndekslerine Giren Dergi)
An algorithm
utilizing four basic processes was described for chemical oil spill dispersion.
Initial dispersion was calculated using a modified Delvigne equation adjusted
to chemical dispersion, then the dispersion was distributed over the mixing
depth, as predicted by the wave height. Then the droplets rise to the surface
according to Stokes’ law. Oil on the surface, from the rising oil and that
undispersed, is re-dispersed. The droplets in the water column are subject to
coalescence as governed by the Smoluchowski equation. A loss is invoked to
account for the production of small droplets that rise slowly and are not
re-integrated with the main surface slick. The droplets become less dispersible
as time proceeds because of increased viscosity through weathering, and by
increased droplet size by coalescence. These droplets rise faster as time
progresses because of the increased size. Closed form solutions were provided
to allow practical limits of dispersibility given inputs of oil viscosity and
wind speed. Discrete solutions were given to calculate the amount of oil in the
water column at specified points of time. Regression equations were provided to
estimate oil in the water column at a given time with the wind speed and oil
viscosity. The models indicated that the most important factor related to the
amount of dispersion, was the mixing depth of the sea as predicted from wind
speed. The second most important factor was the viscosity of the starting oil.
The algorithm predicted the maximum viscosity that would be dispersed given
wind conditions. Simplified prediction equations were created using regression.