Pumping and mixing in active pores

Abstract

We show both numerically and analytically that a chemically patterned active pore can act as a micro/nano-pump for fluids, even if it is fore-aft symmetric. This is possible due to a spontaneous symmetry breaking which occurs when advection rather than diffusion is the dominant mechanism of solute transport. We further demonstrate that, for pumping and tuning the flow rate, a combination of geometrical and chemical inhomogeneities is required. For certain parameter values, the flow is unsteady, and persistent oscillations with a tunable frequency appear. Finally, we find that the flow may lose its axial symmetry and hence promotes mixing in the low Reynolds number regime.

16 pages, 8 figures, 1 video ; additional discussion

References in corpus (5)

• Self-motile colloidal particles: from directed propulsion to random walk
• Phoretic self-propulsion at finite Péclet numbers
• Light Activated Self-Propelled Colloids
• Autophoretic locomotion from geometric asymmetry
• Spontaneous onset of convection in a uniform phoretic channel

Cited by in corpus (4)

• Interfacial activity dynamics of confined active droplets
• Self-generated electrokinetic flows from active-charged boundary patterns
• Turning catalytically active pores into active pumps
• Diffusioosmotic corner flows