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arXiv · 1307.3238

Enhanced flow of core-softened fluids through nanotubes

J. R. Bordin·J. S. Soares Jr·A. Diehl·M. C. Barbosa
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Abstract

We investigate through non-equilibrium molecular dynamic simulations the flow of core-softened fluids inside nanotubes. Our results reveal a anomalous increase of the overall mass flux for nanotubes with sufficiently smaller radii. This is explained in terms of a transition from a single-file type of flow to the movement of an ordered-like fluid as the nanotube radius increases. The occurrence of a global minimum in the mass flux at this transition reflects the competition between the two characteristics length scales of the core-softened potential. Moreover, by increasing further the radius, another substantial change in the flow behavior, which becomes more evident at low temperatures, leads to a local minimum in the overall mass flux. Microscopically, this second transition results from the formation of a double-layer of flowing particles in the confined nanotube space. These special nano-fluidic features of core-softened particles closely resemble the enhanced flow behavior observed for liquid water inside carbon nanotubes.

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J. R. Bordin, J. S. Soares Jr, A. Diehl, M. C. Barbosa. 2013-07-11. Enhanced flow of core-softened fluids through nanotubes. https://doi.org/10.1063/1.4876555

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