2009 Volume 42 Issue 12 Pages 884-892
We have successfully evaluated the lift velocities of spherical particles with diameters of 0.2–1 μm in crossflow microfiltration. The ascending migration of one or multiple particles that were located in a shear field, in the presence or absence of permeation flux, was computed using Newtonian dynamics and the fluctuating Navier–Stokes equation. In the case of a single particle, we found that the lift velocity was proportional to the square of the shear rate and the cube of the particle size. We also evaluated the lift velocity for a multiparticle system to investigate the effect of particle concentration. We found that the lift velocity tended to decrease as the particle concentration increased. We succeeded in performing the first evaluation of the lift velocity for a multiparticle system in the presence of permeation flux. We also showed that the ascent velocity of a particle is the linear sum of the lift velocity and the permeation flux.