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arXiv · 1103.0166

Growing non-equilibrium length in granular fluids: from experiment to fluctuating hydrodynamics

Giacomo Gradenigo·Alessandro Sarracino·Dario Villamaina·Andrea Puglisi
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Abstract

Velocity correlations in a 2D granular fluid are studied in experiments and numerical simulations. The transverse component of the velocity structure factor reveals two well defined energy scales, associated with the external "bath temperature" $T_b$ and with the internal granular one, $T_g<T_b$, relevant at large and small wavelengths respectively. Experimental and numerical data are discussed within a fluctuating hydrodynamics model, which allows one to define and measure a non-equilibrium coherence length $ξ$, growing with density, that characterizes order in the velocity field.

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Giacomo Gradenigo, Alessandro Sarracino, Dario Villamaina, Andrea Puglisi. 2011-09-20. Growing non-equilibrium length in granular fluids: from experiment to fluctuating hydrodynamics. https://doi.org/10.1209/0295-5075%2F96%2F14004

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