This title appears in the Scientific Report :
2012
Please use the identifier:
http://dx.doi.org/10.1063/1.3689322 in citations.
Please use the identifier: http://hdl.handle.net/2128/7494 in citations.
Diffusion, sedimentation, and rheology of concentrated suspensions of core-shell particles
Diffusion, sedimentation, and rheology of concentrated suspensions of core-shell particles
Short-time dynamic properties of concentrated suspensions of colloidal core-shell particles are studied using a precise force multipole method which accounts for many-particle hydrodynamic interactions. A core-shell particle is composed of a rigid, spherical dry core of radius a surrounded by a unif...
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Personal Name(s): | Abade, G.C. |
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Cichocki, B. / Ekiel-Jezewska, M.L. / Nägele, G. / Wajnryb, E. | |
Contributing Institute: |
Weiche Materie; ICS-3 |
Published in: | The @journal of chemical physics, 136 (2012) S. 104902 |
Imprint: |
Melville, NY
American Institute of Physics
2012
|
Physical Description: |
104902 |
DOI: |
10.1063/1.3689322 |
PubMed ID: |
22423856 |
Document Type: |
Journal Article |
Research Program: |
BioSoft: Makromolekulare Systeme und biologische Informationsverarbeitung |
Series Title: |
Journal of Chemical Physics
136 |
Subject (ZB): | |
Link: |
Get full text Published under German "Allianz" Licensing conditions on 2012-03-09. Available in OpenAccess from 2012-03-09 |
Publikationsportal JuSER |
Please use the identifier: http://hdl.handle.net/2128/7494 in citations.
Short-time dynamic properties of concentrated suspensions of colloidal core-shell particles are studied using a precise force multipole method which accounts for many-particle hydrodynamic interactions. A core-shell particle is composed of a rigid, spherical dry core of radius a surrounded by a uniformly permeable shell of outer radius b and hydrodynamic penetration depth κ(-1). The solvent flow inside the permeable shell is described by the Brinkman-Debye-Bueche equation, and outside the particles by the Stokes equation. The particles are assumed to interact non-hydrodynamically by a hard-sphere no-overlap potential of radius b. Numerical results are presented for the high-frequency shear viscosity, η(∞), sedimentation coefficient, K, and the short-time translational and rotational self-diffusion coefficients, D(t) and D(r). The simulation results cover the full three-parametric fluid-phase space of the composite particle model, with the volume fraction extending up to 0.45, and the whole range of values for κb, and a/b. Many-particle hydrodynamic interaction effects on the transport properties are explored, and the hydrodynamic influence of the core in concentrated systems is discussed. Our simulation results show that for thin or hardly permeable shells, the core-shell systems can be approximated neither by no-shell nor by no-core models. However, one of our findings is that for κ(b - a) ≳ 5, the core is practically not sensed any more by the weakly penetrating fluid. This result is explained using an asymptotic analysis of the scattering coefficients entering into the multipole method of solving the Stokes equations. We show that in most cases, the influence of the core grows only weakly with increasing concentration. |