Pressure-driven flow in parallel-plate nanochannels

A "channel moving" pressure-driven model is proposed to generate a constant pressure gradient in fluid flow. Classical molecular dynamics simulations are carried out to explore the pressure-driven flow in parallel-plate nanochannels with the channel width ranging from 2.611 to 5.595 nm. Considering the slip boundary conditions, relationships among the pressure gradient, mean flow velocity, and the channel width are investigated to couple the atomistic regime to continuum. The results indicate that the pressure-driven flows confined in nanochannels modeled in our simulations can be approximately described by the Navier-Stokes equations while the approximate accuracy increases with enlarging the channel width.