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arXiv · 1610.08667

Heat flux of a granular gas with homogeneous temperature

Nagi Khalil
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Abstract

A steady state of a granular gas with homogeneous granular temperature, no mass flow, and nonzero heat flux is studied. The state is created by applying an external position--dependent force or by enclosing the grains inside a curved two--dimensional silo. At a macroscopic level, the state is identified with one solution to the inelastic Navier--Stokes equations, due to the coupling between the heat flux induced by the density gradient and the external force. On the contrary, at the mesoscopic level, by exactly solving a BGK model or the inelastic Boltzmann equation in an approximate way, a one--parametric family of solutions is found. Molecular dynamics simulations of the system in the quasi--elastic limit are in agreement with the theoretical results.

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Nagi Khalil. 2016-10-27. Heat flux of a granular gas with homogeneous temperature. https://doi.org/10.1088/1742-5468%2F2016%2F10%2F103209

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