Spontaneous development of 3-D structure in sheared granular flows

James F. Lutsko

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arXiv · cond-mat/0403551

Spontaneous development of 3-D structure in sheared granular flows

James F. Lutsko

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Abstract

Computer simulations of sheared granular fluids, modeled as inelastic hard spheres, are presented which show signs of a uniquely three-dimensional instabilty. In the stable regime, a linear velocity profile, $v_{x}=ay$, with shear rate $a$ is established using Lees-Edwards boundary conditions. In the unstable regime, the velocity profile aquires a dependence on the third dimension of the form $v_{x}=ay+sin(2πz/L)$ in a cubic box with sides of length $L$. An analysis of the linearized Navier-Stokes equations shows the presence of an instability and gives a simple expression for the critical wavevector which is quantitatively consistent with the results of simulations and which indicates that the instability persists at low densities.

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James F. Lutsko. 2004-03-22. Spontaneous development of 3-D structure in sheared granular flows. https://arxiv.org/abs/cond-mat/0403551

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