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arXiv · 0711.0347

A theoretical analysis of the resolution due to diffusion and size-dispersion of particles in deterministic lateral displacement devices

Martin Heller·Henrik Bruus
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Abstract

We present a model including diffusion and particle-size dispersion for separation of particles in deterministic lateral displacement devices also known as bumper arrays. We determine the upper critical diameter for diffusion-dominated motion and the lower critical diameter for pure convection-induced displacement. Our model explains the systematic deviation, observed for small particles in several experiments, from the critical diameter for separation given by simple laminar flow considerations.

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Martin Heller, Henrik Bruus. 2007-11-02. A theoretical analysis of the resolution due to diffusion and size-dispersion of particles in deterministic lateral displacement devices. https://doi.org/10.1088/0960-1317%2F18%2F7%2F075030

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