Surfactant-influenced oil–water slip and flow in nanochannels studied by molecular dynamics and theoretical modeling

This work uses molecular dynamics (MD) methods to investigate oil–water two-phase flow in hydrophilic nanochannels with surfactants adsorbed at the interface. We reveal two new discontinuous effects of nanoscale fluid flow: (i) velocity distribution water layer is not a univariate function pressure gradient, and (ii) apparent viscosity interface region surfactant concentration gradient. Based on MD results, layered theoretical model describing developed. The provides quantitative two-dimensional functions for slip mass flux gradient concentration. Surfactants significantly inhibit reduce flux. study thus important insights into numerical models shale or tight oil production predictions.