Numerical Algorithm to Compute the Effects of Breaking Waves on Surface Oil Spilled at Sea

Abstract

The purpose of this project has been to extend earlier work on the entrainment of oil into higher viscosity, non-Newtonian regions. The key deliverable is an algorithm for modeling natural entrainment of spilled oil at sea, extending the range of application beyond the 100 – 1000 cP limit of the earlier work. Equations were developed for droplet size distribution as a function of oil film thickness, wave amplitude, oil viscosity, and oil-water interfacial tension. Combined with equations for wave height and period as a functions of wind speed (plus fetch, depth and duration if desired), and whitecap coverage, an algorithm for natural dispersion is presented. This algorithm differs substantially from earlier work in that it is built up from a dimensional analysis of the problem, incorporating both the Weber number and a non-dimensional viscosity group.