A scheme for hybrid molecular dynamics/finite element analysis of thin film lubrication

Abstract

Impressive strides have recently been made in the field of tribology through molecular dynamics (MD) simulations. A convergence of MD and experiment has led to optimism in scientific circles that the mechanisms of friction and boundary lubrication, studied for centuries, can soon be understood and predicted by first principles. However, from the engineering point of view, practical predictive ability seems far away. Toward the eventual goal of applying MD analysis to practical tribological design, we propose a hybrid molecular dynamics–finite element method. Similar approaches have been used in simulating dislocations and other defects in crystalline solids under nano-indenting, and in simulation of reacting flows. In our preliminary study, linkage to MD is established through a variable effective viscosity which increases near the surfaces due to molecular forces. Preliminary results are presented showing an increase in pressure due to the presence of nearby surfaces.