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arXiv · 0802.0055

Velocity Distribution and the Effect of Wall Roughness in Granular Poiseuille Flow

K. C. Vijayakumar·Meheboob Alam
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Abstract

From event-driven simulations of a gravity-driven channel flow of inelastic hard-disks, we show that the velocity distribution function remains close to a Gaussian for a wide range densities (even when the Knudsen number is of order one) if the walls are smooth and the particle collisions are nearly elastic. For dense flows, a transition from a Gaussian to a power-law distribution for the high velocity tails occurs with increasing dissipation in the center of the channel, irrespective of wall-roughness. For a rough wall, the near-wall distribution functions are distinctly different from those in the bulk even in the quasielastic limit.

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K. C. Vijayakumar, Meheboob Alam. 2008-02-01. Velocity Distribution and the Effect of Wall Roughness in Granular Poiseuille Flow. https://doi.org/10.1103/physreve.75.051306

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