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Register a new userBifurcation study for a surface-acoustic-wave driven meniscus
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Added by
Kevin David Joachim Mitas
Publication date
2020
fields
Physics
and research's language is
English
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A thin-film model for a meniscus driven by Rayleigh surface acoustic waves (SAW) is analysed, a problem closely related to the classical Landau-Levich or dragged-film problem where a plate is withdrawn at constant speed from a bath. We consider a mesoscopic hydrodynamic model for a partially wetting liquid, were wettability is incorporated via a Derjaguin (or disjoining) pressure and combine SAW driving with the elements known from the dragged-film problem. For a one-dimensional substrate, i.e., neglecting transversal perturbations, we employ numerical path continuation to investigate in detail how the various occurring steady and time-periodic states depend on relevant control parameters like the Weber number and SAW strength. The bifurcation structure related to qualitative transitions caused by the SAW is analysed with particular attention on the Hopf bifurcations related to the emergence of time-periodic states corresponding to the regular shedding of lines from the meniscus. The interplay of several of these bifurcations is investigated obtaining information relevant to the entire class of dragged-film problems.
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