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arXiv · 1208.5565

Optimal Energy Dissipation in Sliding Friction Simulations

A. Benassi·A. Vanossi·G. E. Santoro·E. Tosatti
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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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A. Benassi, A. Vanossi, G. E. Santoro, E. Tosatti. 2012-08-28. Optimal Energy Dissipation in Sliding Friction Simulations. https://doi.org/10.1007/s11249-012-9936-5

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