A multiscale method for micro/nano flows of high aspect ratio

Matthew Karl Borg, Duncan A. Lockerby, Jason Reese

Research output: Contribution to journalArticle

48 Citations (Scopus)
50 Downloads (Pure)

Abstract

We develop a new multiscale scheme for simulating micro/nano flows of high aspect ratio in the flow direction, e.g. within long ducts, tubes, or channels, of varying section. The scheme couples conventional hydrodynamic conservation equations for mass and momentum-flux with molecular dynamics (MD) in a unified framework. The method is very much different from common 'domain-decomposition' hybrid methods, and is more related to micro-resolution methods, such as the Heterogeneous Multiscale Method. We optimise the use of the computationally-costly MD solvers by applying them only at a limited number of streamwise-distributed cross-sections of the macroscale geometry. The greater the streamwise scale of the geometry, the more significant is the computational speed-up when compared to a full MD simulation. We test our new multiscale method on the case of a converging/diverging nanochannel conveying a simple Lennard-Jones liquid. We validate the results from our simulations by comparing them to a full MD simulation of the same test case.
Original languageEnglish
Pages (from-to)400-413
JournalJournal of Computational Physics
Volume233
DOIs
Publication statusPublished - 15 Jan 2013

Fingerprint

Multiscale Methods
high aspect ratio
Molecular Dynamics
Aspect Ratio
Molecular Dynamics Simulation
Molecular dynamics
Aspect ratio
molecular dynamics
Lennard-Jones
Domain Decomposition
Decomposition Method
Hybrid Method
Conservation
Hydrodynamics
Tube
Speedup
Cross section
Momentum
Optimise
Liquid

Keywords

  • multiscale simulations
  • hybrid method
  • molecular dynamics
  • coupled solvers
  • scale-separation

Cite this

Borg, Matthew Karl ; Lockerby, Duncan A. ; Reese, Jason. / A multiscale method for micro/nano flows of high aspect ratio. In: Journal of Computational Physics. 2013 ; Vol. 233. pp. 400-413.
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A multiscale method for micro/nano flows of high aspect ratio. / Borg, Matthew Karl; Lockerby, Duncan A. ; Reese, Jason.

In: Journal of Computational Physics, Vol. 233, 15.01.2013, p. 400-413.

Research output: Contribution to journalArticle

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