On the effect of confined fluid molecular structure on nonequilibrium phase behaviour and friction

摘要: A detailed understanding of the behaviour confined fluids is critical to a range industrial applications, for example control friction in engineering components. In this study, combination tribological experiments and nonequilibrium molecular dynamics simulations has been used investigate effect base fluid structure on phase friction. An extensive parameter including several lubricant traction molecules subjected pressures (0.5–2.0 GPa) strain rates (104–1010 s−1) typical elastohydrodynamic lubrication regime, reveals clear relationships between flow behaviour. Lubricants, which are flexible, broadly linear molecules, give low coefficients that increase with rate pressure both simulations. Conversely, fluids, based inflexible cycloaliphatic groups, high only weakly depend pressure. The observed differences can be rationalised through stronger shear localisation Higher lead more pronounced localisation, whilst increased widening sheared region. methods utilised study have clarified physical mechanisms important show significant potential improving prediction developing new it.