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Hydrodynamic Modes for Granular Gases

James W. Dufty·J. Javier Brey
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Abstract

The eigenfunctions and eigenvalues of the linearized Boltzmann equation for inelastic hard spheres (d=3) or disks (d=2) corresponding to d+2 hydrodynamic modes, are calculated in the long wavelength limit for a granular gas. The transport coefficients are identified and found to agree with those from the Chapman-Enskog solution. The dominance of hydrodynamic modes at long times and long wavelengths is studied via an exactly solvable kinetic model. A collisional continuum is bounded away from the hydrodynamic spectrum, assuring a hydrodynamic description at long times. The bound is closely related to the power law decay of the velocity distribution in the reference homogeneous cooling state.

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BibTeXRIS

James W. Dufty, J. Javier Brey. 2003-02-10. Hydrodynamic Modes for Granular Gases. https://doi.org/10.1103/physreve.68.030302

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