The mechanics of particle accumulation structures in thermocapillary flows
Institute of Fluid Mechanics and Heat Transfer,
Vienna University of Technology,
Revised: 25 January 2011
Published online: 9 March 2011
The motion of small particles suspended in a cylindrical thermocapillary liquid bridge is considered. Owing to geometry and surface stresses the streamlines gather near the cylindrical free surface and provoke particle–free-surface collisions. We show numerically that tracers which are perfect but of finite size can accumulate on closed trajectories. A simple model is proposed to explain the attraction of particles to the closed trajectory based on the flow topology in the vicinity of a closed streamline which comes sufficiently close to the free surface and on particle–free-surface collisions which transfer particles among different streamlines.
© EDP Sciences, Springer-Verlag, 2011