Fourier's Law for a Granular Fluid

James W. Dufty

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arXiv · 0707.1116

Fourier's Law for a Granular Fluid

James W. Dufty

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Abstract

Newton' viscosity law for the momentum flux and Fourier's law for the heat flux define Navier-Stokes hydrodynamics for a simple, one component fluid. There is ample evidence that a hydrodynamic description applies as well to a mesoscopic granular fluid with the same form for Newton's viscosity law. However, theory predicts a qualitative difference for Fourier's law with an additional contribution from density gradients even at uniform temperature. The reasons for the absence of such terms for normal fluids are indicated, and a related microscopic explanation for their existence in granular fluids is presented.

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James W. Dufty. 2007-07-07. Fourier's Law for a Granular Fluid. https://arxiv.org/abs/0707.1116

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