Transport and sedimentation of solid particles in Bénard hexagonal cells
Technopôle de Château-Gombert, Polytech'Marseille (IUSTI - CNRS UMR 6595), 5 rue Enrico Fermi, 13453, Marseille, France
* e-mail: Bernard.Porterie@polytech.univ-mrs.fr
Accepted: 22 July 2005
Published online: 27 September 2005
The motion of particles moving under gravity in the velocity field of a liquid in a Bénard hexagonal cell is studied experimentally and numerically for Stokes flow conditions. We then explain the settlement of particles in the centers of cells to form a regular quincunx. It is found that sedimentation also occurs preferentially along the lines connecting the centers of adjacent cells to form a triangle deposition tessellation. Finally, it is explained why particles occupy the central part of each convective cell while the peripheral part of the cell quickly becomes limpid. Numerical results are in agreement with the experimental observations of Bénard and those of the present study.
PACS: 44.25.+f Natural convection – / 47.20.Dr Surface-tension-driven instability – / 47.55.Kf Multiphase and particle-laden flows –
© EDP Sciences, Società Italiana di Fisica and Springer-Verlag, 2005