Hydrodynamics and Brownian motions of a spheroid near a rigid wall

Abstract

Articles you may be interested in PHYSICS 142, 194901 (2015) Hydrodynamics and Brownian motions of a spheroid near a rigid wall In this work, we study in detail the hydrodynamics and the Brownian motions of a spheroidal particle suspended in a Newtonian fluid near a flat rigid wall. We employ 3D Finite Element Method (FEM) simulations to compute how the mobility tensor of the spheroid varies with both the particle-wall separation distance and the particle orientation. We then study the Brownian motion of the spheroid by means of a discretized Langevin equation. We specifically focus on the additional drift terms arising from the position and orientational dependence of the mobility matrix. In this respect, we also propose a numerically convenient approximation of the orientational divergence of the mobility matrix that is required in the solution of the Langevin equation. Our results illustrate that both hydrodynamics and Brownian motions of a spheroidal particle near a confining wall display novel features from those of a sphere in the same type of confinement. C 2015 AIP Publishing LLC. [http://dx

Near-wall diffusion tensor of an axisymmetric colloidal particle

“…23 By that we have also verified earlier theoretical developments and recent numerical predictions. 22 Our results are in agreement with numerical calculations even in the case when L/H ∼ O(1), rendering them practical for large and moderate wall-particle distances. …”

“…The structure of the near-wall tensors is identical to that given in Ref. 22. In the body-fixed frame of reference RW, the correction tensors in Eqs.…”

Focusing and Sorting of Ellipsoidal Magnetic Particles in Microchannels

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Short-time dynamics of monomers and dimers in quasi-two-dimensional colloidal mixtures

“…It is well-known that HI and the Brownian motion of colloidal particles are dramatically affected by the presence of walls [12,26]. In particular, several experiments have been carried out to understand the singleparticle diffusion near to a flat wall [27][28][29].…”

“…As mentioned previously, the dynamics of nonspherical colloids is nowadays a challenging topic of paramount importance within the context of condensed matter physics. From theoretical point of view, recent advances have been achieved by solving the NavierStokes equations in the limit of low Reynolds number, Re ≪ 1, for anisotropic particles [26,30]. In particular, Zabarankin [30] calculated the drag force and the resisting torque experienced by a dicolloid-like particle at the bulk.…”