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Confinement-induced enhancement of diffusiophoretic forces on self-propellers
Abstract Book of the XXIII IUPAP International Conference on Statistical Physics, Genova, Italy, (9-13 July 2007)
Аннотация
For applications in, e.g., drug-delivery systems or micromechanics,
one of the most challenging problems at this stage is to develop ways
to enable small-scale objects to perform autonomous, controlled motion.
Exploiting a variety of physical and chemical processes, a number of
``proof of principle'' proposals of such micro-engines have been made
(for both translational and rotational motion).
Employing as a working example a recently proposed simple model of
a self-propelling device driven by chemical reactions taking place on
some parts of its surface 1, we study the effect of spatial confinement
on the magnitude of propulsive diffusiophoretic forces acting on
such a particle. We demonstrate that the motive force significantly
increases in the presence of confining walls, even in the case of the
simplest possible confining geometry, that is, of a wall with the same
shape as the particle, and we also show that such effects become even
more pronounced in two-dimensional systems. We further present numerical
results for the technologically relevant case of a spherical particles
within a cylindrical pore.
References:\\
1) Golestanian R., Liverpool T. B., and Ajdari A., Phys. Rev. Lett. 94, 220801 (2005).
