Effect of lubricants on the rotational transmission between solid-state gears.

Huang-Hsiang Lin,Gianaurelio Cuniberti,Alexander Croy,Rafael Gutiérrez,Jonathan Heinze

doi:10.3762/bjnano.13.3

Abstract

Lubricants are widely used in macroscopic mechanical systems to reduce friction and wear. However, on the microscopic scale, it is not clear to what extent lubricants are beneficial. Therefore, in this study, we consider two diamond solid-state gears at the nanoscale immersed in different lubricant molecules and perform classical MD simulations to investigate the rotational transmission of motion. We find that lubricants can help to synchronize the rotational transmission between gears regardless of the molecular species and the center-of-mass distance. Moreover, the influence of the angular velocity of the driving gear is investigated and shown to be related to the bond formation process between gears.

Highlights

In mechanical systems, lubrication is the most common way to reduce friction and wear [1,2,3,4]
In Results and Discussion, we investigate the rotational transmission between diamondbased solid-state gears immersed in different lubricant molecules and with various center-of-mass distances
We present the results for the rotational transmission with and without lubricant and discuss the effect of the center-of-mass distance and of the angular velocity

Summary

Introduction

Lubrication is the most common way to reduce friction and wear [1,2,3,4]. The desirable lubrication regime would be hydrodynamic or elastohydrodynamic lubrication in the Stribeck curve [5]. The former corresponds to the situation that surfaces are completely separated by a fluid. The latter is similar but surface deformations are taken into account due to high pressure at intermediate sliding velocities. In the case of the gear–oil–gear system, several studies based on the CFD simulation have been reported [11,12,13,14,15,16,17,18]. Most of the simulations for this type of problem are carried out with fixed rotational speed for both

Methods

Results

Conclusion