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arXiv · 1402.4757

Navier-Stokes transport coefficients for driven inelastic Maxwell models

Moisés G. Chamorro·Vicente Garzó·Francisco Vega Reyes
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Abstract

We calculate in this work the Navier-Stokes transport coefficients from the Boltzmann equation for $d$-dimensional inelastic Maxwell models. By granular gas we mean here a low density system of identical spheres that lose a fraction of their kinetic energy after collisions. In the present work, the granular gas is fluidized by the presence of a thermostat that aides the system to reach a steady state. The thermostat is composed by two terms: a random force and a drag force. The combined action of both forces, that act homogeneously on the granular gas, tries to mimic the interaction of the set of particles with a surrounding fluid. The Chapman-Enskog method is applied to solve the inelastic Boltzmann equation to first order in the deviations of the hydrodynamic fields from their values in the homogeneous steady state. Since the collisional cooling cannot be compensated locally for by the heat produced by the driving forces, the reference (zeroth-order) distribution function $f^{(0)}$ depends on time through its dependence on the granular temperature. To simplify the analysis and obtain explicit forms for the transport coefficients, the steady state conditions are considered. A comparison with previous results obtained for inelastic hard spheres is also carried out.

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Moisés G. Chamorro, Vicente Garzó, Francisco Vega Reyes. 2014-04-15. Navier-Stokes transport coefficients for driven inelastic Maxwell models. https://doi.org/10.1088/1742-5468%2F2014%2F06%2Fp06008

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