Self-charging of identical grains in the absence of an external field

Ryuta Yoshimatsu; Nuno Araújo; Gerhard Wurm; Hans Herrmann; Troy Shinbrot

doi:10.1038/srep39996

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arXiv · 1608.03210

Self-charging of identical grains in the absence of an external field

Ryuta Yoshimatsu·Nuno Araújo·Gerhard Wurm·Hans Herrmann·Troy Shinbrot

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Abstract

We investigate the electrostatic charging of an agitated bed of identical grains using simulations, mathematical modeling, and experiments. We simulate charging with a discrete-element model including electrical multipoles and find that infinitesimally small initial charges can grow exponentially rapidly. We propose a mathematical Turing model that defines conditions for exponential charging to occur and provides insights into the mechanisms involved. Finally, we confirm the predicted exponential growth in experiments using vibrated grains under microgravity, and we describe novel predicted spatiotemporal states that merit further study.

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Ryuta Yoshimatsu, Nuno Araújo, Gerhard Wurm, Hans Herrmann, Troy Shinbrot. 2016-08-10. Self-charging of identical grains in the absence of an external field. https://doi.org/10.1038/srep39996

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