caa a22 4500 606166610 CHVBK 20210128100659.0 cr unu---uuuuu 210128e20151001xx s 000 0 eng 10.1007/s10665-014-9735-0 doi (NATIONALLICENCE)springer-10.1007/s10665-014-9735-0 Surfactant spreading on a thin liquid film: reconciling models and experiments [Elektronische Daten] [Ellen Swanson, Stephen Strickland, Michael Shearer, Karen Daniels] The spreading dynamics of surfactant molecules on a thin fluid layer is of both fundamental and practical interest. A mathematical model formulated by Gaver and Grotberg [J Fluid Mech 235:399-414, 1992] describing the spreading of a single layer of insoluble surfactant has become widely accepted, and several experiments on axisymmetric spreading have confirmed its predictions for both the height profile of the free surface and the spreading exponent (the radius of the circular area covered by surfactant grows as $$t^{1/4}$$ t 1 / 4 ). However, these prior experiments utilized primarily surfactant quantities exceeding (sometimes far exceeding) a monolayer. In this paper, we report that this regime is characterized by a mismatch between the timescales of the experiment and model and, additionally, find that the spatial distribution of surfactant molecules differs substantially from the model prediction. For experiments performed in the monolayer regime for which the model was developed, the surfactant layer is observed to have a spreading exponent of less than $$1/10$$ 1 / 10 , far below the predicted value, and the surfactant distribution is also in disagreement. These findings suggest that the model is inadequate for describing the spreading of insoluble surfactants on thin fluid layers. Springer Science+Business Media Dordrecht, 2014 Experiment nationallicence Model nationallicence Surfactant nationallicence Thin liquid film nationallicence Swanson Ellen Department of Mathematics, Centre College, 40422, Danville, KY, USA aut Strickland Stephen Department of Physics, North Carolina State University, 27695, Raleigh, NC, USA aut Shearer Michael Department of Mathematics, North Carolina State University, 27695, Raleigh, NC, USA aut Daniels Karen Department of Physics, North Carolina State University, 27695, Raleigh, NC, USA aut Journal of Engineering Mathematics Springer Netherlands 94/1(2015-10-01), 63-79 0022-0833 94:1<63 2015 94 10665 https://doi.org/10.1007/s10665-014-9735-0 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s10665-014-9735-0 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Swanson Ellen Department of Mathematics, Centre College, 40422, Danville, KY, USA aut NATIONALLICENCE 700 1- Strickland Stephen Department of Physics, North Carolina State University, 27695, Raleigh, NC, USA aut NATIONALLICENCE 700 1- Shearer Michael Department of Mathematics, North Carolina State University, 27695, Raleigh, NC, USA aut NATIONALLICENCE 700 1- Daniels Karen Department of Physics, North Carolina State University, 27695, Raleigh, NC, USA aut NATIONALLICENCE 773 0- Journal of Engineering Mathematics Springer Netherlands 94/1(2015-10-01), 63-79 0022-0833 94:1<63 2015 94 10665