科研之友
微信
新浪微博
Facebook
分享链接
摘要
The impact of the porous shell on the hydrodynamics of a core-shell (soft) particle is studied for low to moderate values of Reynolds number. The Reynolds number is based on the migration speed and radius of the core-shell particle. The influence of shell-to-core thickness ratio and permeability of the shell at a fixed Reynolds number is analyzed. The flow within the porous shell is governed by the Darcy-Brinkman-Forchheimer extended model and the Navier-Stokes equations in the clear fluid region. A single-domain approach in which two sets of equations for the fluid and the porous regions are combined into one set by introducing a binary parameter is adopted. Our numerical results are in excellent agreement with the analytic solution based on the Stokes-Brinkman model for a lower range of the Reynolds number. The computed solution based on the present model deviates from the linear model for a Reynolds number beyond 0.1. We found that the nonlinearity effects become strong as the permeability of the shell decreases. The influence of the Reynolds number on hydrodynamics and flow separation from the core-shell particle is studied. Our result for low Reynolds number shows that the mechanism of sustained solute release from the shell is initially dominated by diffusion; however, the fluid inertia effect becomes strong at the later stage, and a plume of solute is observed even at a low Reynolds number (Re < 1).
- 出版日期2015-3
