Molecular Dynamics Simulation of Valveless Pumping in a Closed Nanofluidic Tube System: A Study of the Local Streaming Velocity

摘要

In this paper we perform a realistic nonequilibrium molecular dynamics simulation of valveless pumping in a closed nanofluidic tube system. It is shown that the simple pumping mechanism can generate a uni-directional mean flow on very small length and times scales, thereby overcoming the technical difficulties often encountered when manufacturing more complex pumping devices. From the molecular dynamics simulation we obtain the spatio temporal dynamics of the pressure. The molecular dynamics results are substituted into the Navier-Stokes equation and we are then able to extract the local streaming velocity profiles sufficiently far away from the pumping device. The mean streaming velocity is compared with molecular dynamics data showing excellent agreement. Detailed knowledge about these profiles will be valuable for future investigation of this remarkable system.