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arXiv · 0801.2851

Ellipsoidal particles at fluid interfaces

H. Lehle·E. Noruzifar·M. Oettel
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Abstract

For partially wetting, ellipsoidal colloids trapped at a fluid interface, their effective, interface--mediated interactions of capillary and fluctuation--induced type are analyzed. For contact angles different from 90$^o$, static interface deformations arise which lead to anisotropic capillary forces that are substantial already for micrometer--sized particles. The capillary problem is solved using an efficient perturbative treatment which allows a fast determination of the capillary interaction for all distances between and orientations of two particles. Besides static capillary forces, fluctuation--induced forces caused by thermally excited capillary waves arise at fluid interfaces. For the specific choice of a spatially fixed three--phase contact line, the asymptotic behavior of the fluctuation--induced force is determined analytically for both the close--distance and the long--distance regime and compared to numerical solutions.

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H. Lehle, E. Noruzifar, M. Oettel. 2008-01-18. Ellipsoidal particles at fluid interfaces. https://doi.org/10.1140/epje%2Fi2007-10314-1

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