Abstract
Inertial microfluidics is regarded as a promising approach to facilitate precise, robust and continuous manipulation of particles through inertial focusing of particles in microchannels. Although there is a need to gain rich insights into the focusing dynamics of particles, it has been hardly studied numerically. In this study, the complex focusing dynamics of particles is simulated numerically for multi-particle suspensions in confined microchannels. To this end, we develop a new method that couples the discrete element method (DEM) with the direct numerical simulation (DNS). This method is referred to as the DEM–DNS method. In order to validate the DEM–DNS method, we then investigate complex dependence of particle behaviour on Reynolds number and channel geometries. With good agreement between the numerical results and existing observations, it is shown for the first time that the DEM–DNS method can simulate the counterintuitive focusing dynamics of particles. This study thus establishes that the DEM–DNS method is a powerful tool to examine the focusing dynamics of particles in inertial microfluidics.
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Acknowledgements
This study was financially supported by Kozo Keikaku Engineering Inc. and by a research grant from Hosokawa Powder Technology Foundation. The authors acknowledge technical support from Dr. Xiaosong Sun and valuable comments from Prof. Masumi Yamada. We have no conflict of interest to declare.
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This article is part of the Topical Collection on: Understanding granular media—from fundamentals and simulations to industrial application.
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Udono, H., Sakai, M. A numerical study on dynamic inertial focusing of microparticles in a confined flow. Granular Matter 19, 79 (2017). https://doi.org/10.1007/s10035-017-0758-x
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DOI: https://doi.org/10.1007/s10035-017-0758-x