1Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 2University of Chinese Academy of Sciences, Beijing 100049 3College of Computer Science and Information Engineering, Guangxi Normal University, Guilin 541004 4Department of Physics, Zhejiang Normal University, Jinhua 321004
Abstract：A biconcave particle suspended in a Poiseuille flow is investigated by the multiple-relaxation-time lattice Boltzmann method with the Galilean-invariant momentum exchange method. The lateral migration and equilibrium of the particle are similar to the Segré-Silberberg effect in our numerical simulations. Surprisingly, two lateral equilibrium positions are observed corresponding to the releasing positions of the biconcave particle. The upper equilibrium positions significantly decrease with the increasing Reynolds number, whereas the lower ones are almost insensitive to the Reynolds number. Interestingly, the regular wave accompanied by nonuniform rotation is exhibited in the lateral movement of the biconcave particle. It can be attributed to the fact that the biconcave shape in various postures interacts with the parabolic velocity distribution of the Poiseuille flow. A set of contours illustrate the dynamic flow field when the biconcave particle has successive postures in a rotating period.
2013, Vol. 30 
