Enhancement of flow mixing in micro and nano channels

Abstract

The aim is to increase the mixing potential of ion species in micro and nano channels with heterogeneous surface potential. We discuss the generation of vortical flow, due to the presence of wall heterogeneity at different locations in the channel. The flow characteristics are obtained by numerical solution of the Poisson equation, the Nernst--Planck equation, and the Navier--Stokes equation, simultaneously. A numerical method based on the pressure correction iterative algorithm is adopted to compute the flow field and mole fraction of the ions. The strong recirculation vortices which appear above the heterogeneities generate a strong pressure gradient which increases mixing performance. References

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