title: Unsteady non-Newtonian hydrodynamics in granular gases.
abstract: The temporal evolution of a dilute granular gas, both in a compressible flow (uniform longitudinal flow) and in an incompressible flow (uniform shear flow), is investigated by means of the direct simulation Monte Carlo method to solve the Boltzmann equation. Emphasis is laid on the identification of a first "kinetic" stage (where the physical properties are strongly dependent on the initial state) subsequently followed by an unsteady "hydrodynamic" stage (where the momentum fluxes are well-defined non-Newtonian functions of the rate of strain). The simulation data are seen to support this two-stage scenario. Furthermore, the rheological functions obtained from simulation are well described by an approximate analytical solution of a model kinetic equation.
authors.affiliation: Departamento de Tecnología de Computadores y Comunicaciones, Universidad de Extremadura, E-06800 Mérida, Spain. aavivas@unex.es
authors.forename: Antonio
authors.initials: A
authors.lastname: Astillero
authors.forename: Andrés
authors.initials: A
authors.lastname: Santos
mesh_terms: D003102:Colloids / Q000737:chemistry*; D003198:Computer Simulation; D005740:Gases / Q000737:chemistry*; D008956:Models, Chemical; D008958:Models, Molecular; D015233:Models, Statistical
chemical_list: D003102:Colloids; D005740:Gases