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Chapman-Enskog expansion about nonequilibrium states: the sheared granular fluid

James F. Lutsko
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Abstract

The Chapman-Enskog method of solution of kinetic equations, such as the Boltzmann equation, is based on an expansion in gradients of the deviations fo the hydrodynamic fields from a uniform reference state (e.g., local equilibrium). This paper presents an extension of the method so as to allow for expansions about \emph{arbitrary}, far-from equilibrium reference states. The primary result is a set of hydrodynamic equations for studying variations from the arbitrary reference state which, unlike the usual Navier-Stokes hydrodynamics, does not restrict the reference state in any way. The method is illustrated by application to a sheared granular gas which cannot be studied using the usual Navier-Stokes hydrodynamics.

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BibTeXRIS

James F. Lutsko. 2005-11-06. Chapman-Enskog expansion about nonequilibrium states: the sheared granular fluid. https://doi.org/10.1103/physreve.73.021302

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