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Spontaneous Ratchet Effect in a Granular Gas

Devaraj van der Meer·Peter Reimann·Ko van der Weele·Detlef Lohse
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Abstract

The spontaneous clustering of a vibrofluidized granular gas is employed to generate directed transport in two different compartmentalized systems: a "granular fountain" in which the transport takes the form of convection rolls, and a "granular ratchet" with a spontaneous particle current perpendicular to the direction of energy input. In both instances, transport is not due to any system-intrinsic anisotropy, but arises as a spontaneous collective symmetry breaking effect of many interacting granular particles. The experimental and numerical results are quantitatively accounted for within a flux model.

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Devaraj van der Meer, Peter Reimann, Ko van der Weele, Detlef Lohse. 2004-04-07. Spontaneous Ratchet Effect in a Granular Gas. https://doi.org/10.1103/physrevlett.92.184301

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