On the validity of linear hydrodynamics for low-density granular flows described by the Boltzmann equation

The direct Monte Carlo simulation method is used to check the validity of the hydrodynamic description of a low-density granular flow in the linear region about the homogeneous cooling state. Good agreement is found between the simulation results and the hydrodynamic equations obtained recently from the Boltzmann equation by using a generalized Chapman-Enskog procedure. In particular, the dependence of the transport coefficients on the coefficient of restitution predicted by the theory is verified.Grant No. PB98-1124 from the Dirección General de Investigación Científica y Técnica (Spain)