Research Grant Report
Studies on Dynamics of Flexible Fibers in a Binary Fluid
2020 Volume 28 Pages 55-63
Details
2020 Volume 28 Pages 55-63
Most of the polymeric materials used in industry are multicomponent systems, and structural reinforcement and new functions are added to them by adding fillers with various properties and shapes. When fibers or rod-like particles are added to a polymeric material, their density and orientation distribution have a significant effect on the physical properties. Therefore, it is particularly important to predict and control the phase separation and aggregation/orientation behavior of polymeric and particulate dispersions. In this study, flexible fibrous particles dispersed in one- and two-component fluids were modeled and numerically simulated using the Smoothed Profile Method (SPM) (Nakayama Y., 2008). The time evolution of the relative viscosity in the start-up shear flow was calculated for fibers dispersed in a single component fluid, and the relation between their orientation and the viscosity was made clear. The calculation results agreed well with the experimental results. It was also found that the orientation of the fibrous particles dispersed in a two-component fluid depends not only on the fluid flow but also on the affinity of the particles to each fluid. In addition, depending on the affinity of the particles to the fluid components, the size and the shape of the phase separated domain are found to be quite different from those in the absence of the fibrous particles.
