Molecular dynamics simulation study of friction force and torque on a rough spherical particle

Swapnil C. Kohale, Rajesh Khare

Research output: Contribution to journalArticlepeer-review

11 Scopus citations

Abstract

Recent developments in techniques of micro- and nanofluidics have led to an increased interest in nanoscale hydrodynamics in confined geometries. In our previous study [S. C. Kohale and R. Khare, J. Chem. Phys. 129, 164706 (2008)], we analyzed the friction force experienced by a smooth spherical particle that is translating in a fluid confined between parallel plates. The magnitude of three effects-velocity slip at particle surface, the presence of confining surfaces, and the cooperative hydrodynamic interactions between periodic images of the moving particle-that determine the friction force was quantified in that work using molecular dynamics simulations. In this work, we have studied the motion of a rough spherical particle in a confined geometry. Specifically, the friction force experienced by a translating particle and the torque experienced by a rotating particle are studied using molecular dynamics simulations. Our results demonstrate that the surface roughness of the particle significantly reduces the slip at the particle surface, thus leading to higher values of the friction force and hence a better agreement with the continuum predictions. The particle size dependence of the friction force and the torque values is shown to be consistent with the expectations from the continuum theory. As was observed for the smooth sphere, the cooperative hydrodynamic interactions between the images of the sphere have a significant effect on the value of the friction force experienced by the translating sphere. On the other hand, the torque experienced by a spherical particle that is rotating at the channel center is insensitive to this effect.

Original languageEnglish
Article number234706
JournalJournal of Chemical Physics
Volume132
Issue number23
DOIs
StatePublished - Jun 21 2010

Fingerprint Dive into the research topics of 'Molecular dynamics simulation study of friction force and torque on a rough spherical particle'. Together they form a unique fingerprint.

Cite this