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arXiv · 1211.0263

Hydrodynamic forces on steady and oscillating porous particles

Santtu T. T. Ollila·Tapio Ala-Nissila·Colin Denniston
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Abstract

We derive new analytical results for the hydrodynamic force exerted on a sinusoidally oscillating porous shell and a sphere of uniform density in the Stokes limit. The coupling between the spherical particle and the solvent is done using the Debye-Bueche-Brinkman (DBB) model, i.e. by a frictional force proportional to the local velocity difference between the permeable particle and the solvent. We compare our analytical results and existing dynamic theories to Lattice-Boltzmann simulations of full Navier-Stokes equations for the oscillating porous particle. We find our analytical results to agree with simulations over a broad range of porosities and frequencies.

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Santtu T. T. Ollila, Tapio Ala-Nissila, Colin Denniston. 2012-11-01. Hydrodynamic forces on steady and oscillating porous particles. https://doi.org/10.1017/jfm.2012.325

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