Direct investigation of methane nanofluidic microstructure and system dynamics in rough silicon nanochannel

Abstract

The microstructure and system dynamics of methane nanofluidic are important to determine the flow properties. In this study, we use non-equilibrium multiscale molecular dynamics simulation (NEMSMD) to investigate the microstructure and system dynamics of methane nanofluidic confined by rough silicon atomic walls. To capture the detailed atomic microstructure of methane moving in rough nanochannel accurately, the modification of OPLS methane fully atomic model is employed. The average number density distributions of C (H) atom, average velocity profile, velocity autocorrelation function and projection radial distribution function (XOY-, XOZ- and YOZ planes) plots give a clear observation of the impacts of different conditions (roughness, body driving force, fluid–wall interaction strength and cutoff radius) on the methane Poiseuille flow in nanochannel. The projection radial distribution functions and diffusivity appear anisotropic, and seem to be affected more significantly by roughness, fluid–wall interaction strength and cutoff radius than body driving force in the whole channel region. Moreover, the body driving force and cutoff radius also play an important role in methane nanofluidic simulation using NEMSMD. The present simulation results are very meaningful for the design of energy-saving emission reduction nanofluidic devices.