Enhanced flow of core-softened fluids through narrow nanotubes.
We investigate through non-equilibrium molecular dynamic simulations the flow of anomalous fluids inside rigid nanotubes. Our results reveal an 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 characteristic 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 is originated by the formation of a double-layer of flowing particles in the confined nanotube space. These nano-fluidic features give insights about the behavior of confined isotropic anomalous fluids.
Campus Caçapava do Sul, Universidade Federal do Pampa, Av. Pedro Anunciação, s/n, CEP 96570-000, Caçapava do Sul, RS, Brazil.
José Rafael
JR
Bordin
Departamento de Física, Universidade Federal do Ceará, CEP 60451-970, Fortaleza, Ceará, Brazil.
José S
JS
Andrade
Departamento de Física, Instituto de Física e Matemática, Universidade Federal de Pelotas, Caixa Postal 354, CEP 96010-900, Pelotas, RS, Brazil.
Alexandre
A
Diehl
Instituto de Física, Universidade Federal do Rio Grande do Sul, Caixa Postal 15051, CEP 91501-970, Porto Alegre, RS, Brazil.
Marcia C
MC
Barbosa
D003198:Computer Simulation; D055119:Elastic Modulus; D017276:Friction; D006244:Hardness; D044085:Microfluidics / Q000379:methods*; D008956:Models, Chemical; D008958:Models, Molecular; D009038:Motion; D058608:Nanopores / Q000648:ultrastructure*; D043942:Nanotubes / Q000737:chemistry* / Q000648:ultrastructure*; D011312:Pressure; D033081:Shear Strength; D012996:Solutions / Q000737:chemistry*
D012996:Solutions