| Mon October 26th 2009 16:00 ZH286 | Seminar | On the lateral migration of a slightly deformed bubble rising near a vertical plane wall Kazu Sugiyama |
Details:Deformation-induced lateral migration of a bubble slowly rising near a vertical plane wall in a stagnant liquid is numerically investigated. In particular, our focus is set on a situation with a small clearance $c$ between the bubble interface and the wall. Motivated by the fact that experimentally (Takemura et al. (2002, J. Fluid Mech. 461, 277)) measured migration velocities are considerably higher than the velocity estimated by the available analytical solution (Magnaudet et al. (2003, J. Fluid Mech. 476, 115)) using the Fax\'{e}n mirror image technique for $(= a/(a+c))\ll 1$ (here $a$ is the bubble radius). When the clearance is comparable to or smaller than the bubble radius, the numerical analysis based on the boundary-fitted finite-difference approach solving the Stokes equation is performed to complement the experiment. The migration velocity is more affected by the high-order deformation modes with decreasing the gap. The numerical simulations are compared with a theoretical migration velocity obtained from a lubrication study of a nearly spherical drop (Hodges et al. (2004, J. Fluid Mech. Vol. 512)). | ||
