Simulation method to resolve hydrodynamic interactions in colloidal dispersions

Abstract

A new computational method is presented to resolve hydrodynamic interactions acting on solid particles immersed in incompressible host fluids. In this method, boundaries between solid particles and host fluids are replaced with a continuous interface by assuming a smoothed profile.This enabled us to calculate hydrodynamic interactions both efficiently and accurately, without neglecting many-body interactions. The validity of the method was tested by calculating the drag force acting on a single cylindrical rod moving in an incompressible Newtonian fluid. This method was then applied in order to simulate sedimentation process of colloidal dispersions.

Hydrodynamic and electrokinetic effects on the dynamics of charged colloids and macromolecules

“…Therefore both methods are suitable to simulate dense colloid dispersions. The SPM method has the advantage that larger time increments can be selected since the particles are treated as solids rather than high-viscous fluid droplets [52]. Since the microions in both methods are described in a mean-field way by a continuous charge distribution, local charge ordering effects beyond the PoissonBoltzmann (PB) level are not considered.…”

“…In the so-called fluid particle dynamics (FPD) method of Tanaka and Araki [49,50], and in the related smoothed profile method (SPM) of Kim, Nakayama and Yamamoto [51,52], the solvent and the microions are treated on a coarse-grained level as continuous fields, akin to standard electrokinetic theory. Only the colloids are treated explicitly as particles.…”

Crystallization of Brownian Particles from Walls Induced by a Uniform External Force

“…During sedimentation by centrifugal force, the hydrodynamic effects [17][18][19][20] may not be neglected. However, since the centrifugal force in the experiment 13) is much weaker than that in other experiments, [21][22][23][24][25] the hydrodynamic effects may be smaller than those in other experiments.…”

Simulation of binary dispersion system of droplets with size and surface tension difference under Couette flow

“…In this case, their average lateral positions are comparable except for ψ > 0. 5. Finally, open and closed squares represent the case where large droplets are much less floppy than small droplets (Ca 0 =1/160 and Ca 1 =1/64).…”

“…In order to examine solely the effect of size difference without deformation, we have executed simulations for binary suspensions of rigid bodies of different sizes, using Immersed Boundary method [4,5]. Figure 5 shows the results for small and large circular disks suspended in Poiseuille flow.…”