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arXiv · 1212.3937

Rheological effects in the linear response and spontaneous fluctuations of a sheared granular gas

J. Javier Brey·P. Maynar·M. I. Garcia de Soria
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Abstract

The decay of a small homogeneous perturbation of the temperature of a dilute granular gas in the steady uniform shear flow state is investigated. Using kinetic theory based on the inelastic Boltzmann equation, a closed equation for the decay of the perturbation is derived. The equation involves the generalized shear viscosity of the gas in the time-dependent shear flow state, and therefore it predicts relevant rheological effects beyond the quasi-elastic limit. A good agreement is found when comparing the theory with molecular dynamics simulation results. Moreover, the Onsager postulate on the regression of fluctuations is fulfilled.

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J. Javier Brey, P. Maynar, M. I. Garcia de Soria. 2012-12-17. Rheological effects in the linear response and spontaneous fluctuations of a sheared granular gas. https://doi.org/10.1103/physreve.86.061308

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