Abstract
In studies of dispersion, dispersed particles migrate in accordance with the external flows. In this talk, we discuss lateral migrations of particles, whose migration direction is perpendicular to the main flow. In 2D simulations of binary dispersed suspension of large and small fluid droplets in a channel flow, it is found that the large droplets move to the center of channel and the small ones move to the vicinity of the walls when the surface tensions of the large and small droplets are the same. This phenomenon corresponds to the so-called margination. On the other hand, the large droplets move to the wall when the surface tension of large droplets is higher than the tension of the small ones. These results are related to the dynamics of blood, which is mainly composed of platelets, leucocytes and red blood cells. The platelets are smaller and stiffer than the red blood cells and the leucocytes are larger and stiffer than the red blood cells. The platelets and the leucocytes exist near the wall of the blood vessel. We expect an innovation of soft material for particle dispersion systems from the stand point of the lateral migration.
