Solid drops: large capillary deformations of immersed elastic rods.
Under the effect of surface tension, a blob of liquid adopts a spherical shape when immersed in another fluid. We demonstrate experimentally that soft, centimeter-size elastic solids can exhibit a similar behavior: when immersed into a liquid, a gel having a low elastic modulus undergoes large, reversible deformations. We analyze three fundamental types of deformations of a slender elastic solid driven by surface stress, depending on the shape of its cross section: a circular elastic cylinder shortens in the longitudinal direction and stretches transversally; the sharp edges of a square based prism get rounded off as its cross sections tend to become circular; and a slender, triangular based prism bends. These experimental results are compared to analysis and nonlinear simulations of neo-Hookean solids deformed by surface tension and are found to be in good agreement with each other.
Laboratoire Charles Coulomb, UMR 5221, Université Montpellier 2 and CNRS, Place Eugène Bataillon, F-34095 Montpellier Cedex, France.
Serge
S
Mora
Corrado
C
Maurini
Ty
T
Phou
Jean-Marc
JM
Fromental
Basile
B
Audoly
Yves
Y
Pomeau