Modeling friction: from nano to meso scales

Source: arXiv

ABSTRACT The physics of sliding friction is gaining impulse from nano and mesoscale
experiments, simulations, and theoretical modeling. This colloquium reviews
some recent developments in modeling and in atomistic simulation of friction,
covering open-ended directions, unconventional nanofrictional systems, and
unsolved problems.

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Available from: Stefano Zapperi, Sep 28, 2015
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    ABSTRACT: Non-equilibrium molecular dynamics simulations, of crucial importance in sliding friction, are hampered by arbitrariness and uncertainties in the removal of the frictionally generated Joule heat. Building upon general pre-existing formulation, we implement a fully microscopic dissipation approach which, based on a parameter-free, non-Markovian, stochastic dynamics, absorbs Joule heat equivalently to a semi-infinite solid and harmonic substrate. As a test case, we investigate the stick-slip friction of a slider over a two-dimensional Lennard-Jones solid, comparing our virtually exact frictional results with approximate ones from commonly adopted dissipation schemes. Remarkably, the exact results can be closely reproduced by a standard Langevin dissipation scheme, once its parameters are determined according to a general and self-standing variational procedure.
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