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arXiv · 1902.05398

Stokesian dynamics of pill-shaped Janus particles with stick and slip boundary conditions

Q. Sun·E. Klaseboer·B. C. Khoo·D. Y. C. Chan
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Abstract

We study the forces and torques experienced by pill-shaped Janus particles of different aspect ratios where half of the surface obeys the no-slip boundary condition and the other half obeys the Navier slip condition of varying slip lengths. Using a recently developed boundary integral formulation whereby the traditional singular behaviour of this approach is removed analytically, we quantify the strength of the forces and torques experienced by such particles in a uniform flow field in the Stokes regime. Depending on the aspect ratio and the slip length, the force transverse to the flow direction can change sign. This is a novel property unique to the Janus nature of the particles.

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Q. Sun, E. Klaseboer, B. C. Khoo, D. Y. C. Chan. 2019-02-11. Stokesian dynamics of pill-shaped Janus particles with stick and slip boundary conditions. https://doi.org/10.1103/physreve.87.043009

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