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arXiv · 0803.3438

Bulk viscosity of the Lennard-Jones system at the triple point by dynamical Non Equilibrium Molecular Dynamics

Pier Luca Palla·Carlo Pierleoni·Giovanni Ciccotti
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Abstract

Non-equilibrium Molecular Dynamics (NEMD) calculations of the bulk viscosity of the triple point Lennard-Jones fluid are performed with the aim of investigating the origin of the observed disagreement between Green-Kubo estimates and previous NEMD data. We show that a careful application of the Doll's perturbation field, the dynamical NEMD method, the instantaneous form of the perturbation and the "subtraction technique" provides a NEMD estimate of the bulk viscosity at zero field in full agreement with the value obtained by the Green-Kubo formula. As previously reported for the shear viscosity, we find that the bulk viscosity exhibits a large linear regime with the field intensity which confirms the Lennard-Jones fluid as a genuine Newtonian fluid even at triple point.

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Pier Luca Palla, Carlo Pierleoni, Giovanni Ciccotti. 2008-03-25. Bulk viscosity of the Lennard-Jones system at the triple point by dynamical Non Equilibrium Molecular Dynamics. https://doi.org/10.1103/physreve.78.021204

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