Abstract
The transport coefficients for dilute granular gases of inelastic and rough hard disks or spheres with constant coefficients of normal () and tangential () restitution are obtained in a unified framework as functions of the number of translational () and rotational () degrees of freedom. The derivation is carried out by means of the Chapman–Enskog method with a Sonine-like approximation in which, in contrast to previous approaches, the reference distribution function for angular velocities does not need to be specified. The well-known case of purely smooth -dimensional particles is recovered by setting and formally taking the limit . In addition, previous results [G. M. Kremer, A. Santos, and V. Garzó, Phys. Rev. E 90, 022205 (2014)] for hard spheres are reobtained by taking , while novel results for hard-disk gases are derived with the choice . The singular quasismooth limit () and the conservative Pidduck's gas () are also obtained and discussed.
- Received 2 June 2021
- Accepted 17 August 2021
DOI:https://doi.org/10.1103/PhysRevE.104.034901
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