Abstract: The fluid properties under the condition of the solid wall normal oscillations were studied using the molecular dynamics method. The two dimensional Couette flow model made up of copper wall and argon fluid was built. The fluid state of the near wall was simulated under the different oscillation parameters of solid wall and the corresponding fluid velocity field, the density distribution, the potential energy curves and the friction force were obtained. Then the influence mechanism of the wall oscillations on the frictional drag at liquid-solid interface was investigated. The results indicate that the frictional drag between wall and fluid can be reduced effectively by applying normal oscillations for the solid wall and the drag reduction rate is mainly dependent on the oscillation parameters. Meanwhile, the decrease of fluid density near wall leads to the reduction in frictional drag at liquid-solid interface.

Key words: wall oscillations, drag reduction, flow field, molecular dynamics simulation