Quantification of mixing in vesicle suspensions using numerical simulations in two dimensions

Abstract

We study mixing in Stokesian vesicle suspensions in two dimensions on a cylindrical Couette apparatus using numerical simulations. The vesicle flow simulation is done using a boundary integral method, and the advection-diffusion equation for the mixing of the solute is solved using a pseudo-spectral scheme. We study the effect of the area fraction, the viscosity contrast between the inside (the vesicles) and the outside (the bulk) fluid, the initial condition of the solute, and the mixing metric. We compare mixing in the suspension with mixing in the Couette apparatus without vesicles. On the one hand, the presence of vesicles in most cases slightly suppresses mixing. This is because the solute can be only diffused across the vesicle interface and not advected. On the other hand, there exist spatial distributions of the solute for which the unperturbed Couette flow completely fails to mix whereas the presence of vesicles enables mixing. We derive a simple condition that relates the velocity and solute and can be used to characterize the cases in which the presence of vesicles promotes mixing.

Document Details

Document Type
Pub Defense Publication
Publication Date
Feb 01, 2017
Source ID
10.1063/1.4975154

Entities

People

  • Bryan Quaife
  • G. Biros
  • Gökberk Kabacaoğlu

Organizations

  • Air Force Office of Scientific Research
  • Defense Advanced Research Projects Agency
  • Florida State University
  • National Institutes of Health
  • National Science Foundation
  • United States Department of Energy
  • University of Texas at Austin

Tags

Readers

  • Aerosol Science/Aerosol Physics
  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)
  • Ocean-Atmosphere Mesoscale Modeling, Data Assimilation, and Flux Boundary Layers