title: How oil properties and layer thickness determine the entrainment of spilled surface oil.
abstract: Viscosity plays an important role in dispersion of spilled surface oil, so does adding chemical dispersants. For seven different oil grades, entrainment rate and initial droplet size distribution were investigated using a plunging jet apparatus with coupled camera equipment and subsequent image analysis. We found that amount of oil entrained is proportional to layer thickness and largely independent of oil properties: A dispersant dose of 1:200 did not result in a significantly different entrainment rate compared to no dispersants. Oil viscosity had a minor to no influence on entrainment rate, until a certain threshold above which entrainment was impeded. The mean droplet size scales with the modified Weber number as described by Johansen. The obtained results can help improve dispersion algorithms in oil spill fate and transport models, to aid making an informed decision about application of dispersants.
authors.affiliation: Dept. Maritime, Marine, Environment & Safety, NHL University of Applied Sciences, P.O. Box 1080, 8900 CB Leeuwarden, The Netherlands; Environmental Technology sub-department, Wageningen University, P.O. Box 17, 6700 AA Wageningen, The Netherlands. Electronic address: m.zeinstra@nhl.nl.
authors.forename: Marieke
authors.initials: M
authors.lastname: Zeinstra-Helfrich
authors.affiliation: Dept. Maritime, Marine, Environment & Safety, NHL University of Applied Sciences, P.O. Box 1080, 8900 CB Leeuwarden, The Netherlands.
authors.forename: Wierd
authors.initials: W
authors.lastname: Koops
authors.affiliation: Marine Animal Ecology group, Wageningen University, P.O. Box 338, 6700 AH, Wageningen, The Netherlands; Environmental Technology sub-department, Wageningen University, P.O. Box 17, 6700 AA Wageningen, The Netherlands.
authors.forename: Albertinka J
authors.initials: AJ
authors.lastname: Murk
mesh_terms: D008962:Models, Theoretical; D010578:Petroleum; D059392:Petroleum Pollution; D014783:Viscosity; D014874:Water Pollutants, Chemical
chemical_list: D010578:Petroleum; D014874:Water Pollutants, Chemical
keywords: Chemical dispersion; Entrainment; Natural dispersion; Oil properties; Oil spill response