The non-equilibrium molecular dynamics simulation is carried out to investigate the flow properties of liquids confined in nanochannel
especially the flow behaviours and the interaction mechanism of fluid molecules confined between two solid walls as the upper wall moving at different shear velocities
and the temperature of liquids near the stationary lower wall keeping constant. The distributions of velocities
densities and temperatures are obtained for a variety of shear velocity; the relationships of the slip of velocity
the density and the temperature profiles with the shear velocity are analyzed. The simulated results show that with the unceasing increase of the shear velocity
the temperature of liquids near the moving wall increases continuously. The slip is easily observed if the distance from the moving wall is less than 0.8 molecular diameter
and beyond this range the velocity profiles appear quite linear. The different shear velocities do not affect the distribution of densities and the order structures of liquids in nanochannel. The average shear stress is enhanced with the increasing shear velocity.
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references
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