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arXiv · 1701.02484

DEM simulation of granular segregation in two-compartment system under zero gravity

Wenguang Wan·Zhigang Zhou·Jin Zong·Meiying Hou
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Abstract

In this paper, granular segregation in a two-compartment cell in zero gravity is studied numerically by DEM simulation. In the simulation using a virtual window method we find a non-monotonic flux, a function which governs the segregation. A parameter is used to quantify the segregation. The effect of three parameters: the total number of particles N, the excitation strength {\Gamma}, and the position of the window coupling the two compartments, on the segregation {\epsilon} and the waiting time {\tau} are investigated. It is found that the segregation observed in zero gravity exists and does not depend on the excitation strength {\Gamma}. The waiting time {\tau}, however, depends strongly on {\Gamma}: Higher the {\Gamma}, lower the waiting time {\tau}. The simulation results are important in guiding the SJ-10 satellite microgravity experiments.

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Wenguang Wan, Zhigang Zhou, Jin Zong, Meiying Hou. 2017-01-10. DEM simulation of granular segregation in two-compartment system under zero gravity. https://arxiv.org/abs/1701.02484

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