A DCAMM seminar will be presented by
\nProfessor Martin E.R. Shanahan
\n12M, CNRS 5295
\nUniversité de Bordeaux, France
\n
\n
Abstract:
\n
\nThe simple equation attributed to Young describing the equilibrium of a liquid, L, on a solid substrate, S, in the presence of a second, immiscible fluid (which we take to be vapour, V) and involving surface/interfacial tensions, γij, (i, j = S, L, or V) and contact angle, θ, is over two centuries old, yet still hides secrets! Amongst various poorly understood aspects, the role played by the component of liquid surface tension perpendicular to the solid surface, γ sinθ (where γLV = γ, for brevity) has remained unknown for a very long time, or even “forgotten”! We consider here various situations in which γ sinθ cannot be neglected, as well as some observations reported in the lite- rature which can thus, at least in part, be explained by the apparently unbalanced term.
\n
\nWe discuss two specific cases of the problem: that in which the solid is intrinsically “hard” (metal, glass, etc.) yet very thin, and that of a semi-infinite solid but of low elastic modulus (elastomer, gel, etc.).
The problems may be approached either by variational techniques to obtain the configuration of minimal free energy, or by consideration of force balance. In both cases, we obtain equations describing solid deformations due to capillary forces. Some consequences of these deformations are discussed, in particular the stability or instability of solids shapes when in contact with a liquid, recently referred to as “elastocapillary origami”, modification of Young’s equation, and “viscoelastic braking”, i.e. reduction of wetting or dewetting rates on elastomeric solids. We also consider some results to be found in the literature in the light of these studies, including in the context of metallurgy.All interested persons are invited.
\nAll interested persons are invited
X-ALT-DESC;FMTTYPE=text/html:A DCAMM seminar will be presented by
\nProfessor Martin E.R. Shanahan
\n12M, CNRS 5295
\nUniversité de Bordeaux, France
\n
\n
Abstract:
\n
\nThe simple equation attributed to Young describing the equilibrium of a liquid, L, on a solid substrate, S, in the presence of a second, immiscible fluid (which we take to be vapour, V) and involving surface/interfacial tensions, γij, (i, j = S, L, or V) and contact angle, θ, is over two centuries old, yet still hides secrets! Amongst various poorly understood aspects, the role played by the component of liquid surface tension perpendicular to the solid surface, γ sinθ (where γLV = γ, for brevity) has remained unknown for a very long time, or even “forgotten”! We consider here various situations in which γ sinθ cannot be neglected, as well as some observations reported in the lite- rature which can thus, at least in part, be explained by the apparently unbalanced term.
\n
\nWe discuss two specific cases of the problem: that in which the solid is intrinsically “hard” (metal, glass, etc.) yet very thin, and that of a semi-infinite solid but of low elastic modulus (elastomer, gel, etc.).
The problems may be approached either by variational techniques to obtain the configuration of minimal free energy, or by consideration of force balance. In both cases, we obtain equations describing solid deformations due to capillary forces. Some consequences of these deformations are discussed, in particular the stability or instability of solids shapes when in contact with a liquid, recently referred to as “elastocapillary origami”, modification of Young’s equation, and “viscoelastic braking”, i.e. reduction of wetting or dewetting rates on elastomeric solids. We also consider some results to be found in the literature in the light of these studies, including in the context of metallurgy.All interested persons are invited.
\nAll interested persons are invited
URL:http://www.dcamm.dk/da/Kalender/2015/04/Seminar_No_682 DTSTAMP:20260927T042900Z UID:{0115C4AE-74C5-4A54-89F6-74C22007771F}-20150423T110000-20150423T110000 LOCATION: Room 05.060, Aarhus University, Department of Engineering, Inge Lehmanns Gade 10, 8000 Aarhus C END:VEVENT END:VCALENDAR