Orientational correlation and velocity distributions in uniform shear flow of a dilute granular gas

Bishakdatta Gayen; Meheboob Alam

doi:10.1103/physrevlett.100.068002

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arXiv · 0802.0056

Orientational correlation and velocity distributions in uniform shear flow of a dilute granular gas

Bishakdatta Gayen·Meheboob Alam

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Abstract

Using particle simulations of the uniform shear flow of a rough dilute granular gas, we show that the translational and rotational velocities are strongly correlated in direction, but there is no orientational correlation-induced singularity at perfectly smooth ($β=-1$) and rough ($β=1$) limits for elastic collisions ($e=1$); both the translational and rotational velocity distribution functions remain close to a Gaussian for these two limiting cases. Away from these two limits, the orientational as well as spatial velocity correlations are responsible for the emergence of non-Gaussian high velocity tails. The tails of both distribution functions follow stretched exponentials, with the exponents depending on normal ($e$) and tangential ($β$) restitution coefficients.

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Bishakdatta Gayen, Meheboob Alam. 2008-02-01. Orientational correlation and velocity distributions in uniform shear flow of a dilute granular gas. https://doi.org/10.1103/physrevlett.100.068002

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