Molecular dynamics investigation of a model ionic liquid lubricant for automotive applications

Konstantinos Gkagkasa; Veerapandian Ponnuchamyb; Miljan Dašić; Igor Stanković

doi:10.1016/j.triboint.2016.12.017

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arXiv · 1612.08450

Molecular dynamics investigation of a model ionic liquid lubricant for automotive applications

Konstantinos Gkagkasa·Veerapandian Ponnuchamyb·Miljan Dašić·Igor Stanković

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Abstract

In the current work we present a new modelling approach for simulating meso-scopic phenomena related to lubrication of the piston ring-cylinder liner contact. Our geometry allows a variable confinement gap and a varying amount of lubricant in the gap, while avoiding the squeeze-out of the lubricant into vacuum. We have implemented a coarse grain molecular dynamics description of an ionic liquid as a lubricant which can expand into lateral reservoirs. The results have revealed two regimes of lubrication, an elasto-hydrodynamic one under low loads and one with low, velocity-independent specific friction, under high loads. The observed steep rise of normal forces at small plate-to-plate distances is an interesting behaviour that could potentially be exploited for preventing solid-solid contact and wear.

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Konstantinos Gkagkasa, Veerapandian Ponnuchamyb, Miljan Dašić, Igor Stanković. 2016-12-23. Molecular dynamics investigation of a model ionic liquid lubricant for automotive applications. https://doi.org/10.1016/j.triboint.2016.12.017

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