Asynchronous coupling of hybrid models for efficient simulation of multiscale systems

Duncan A. Lockerby*, Alexander Patronis, Matthew K. Borg, Jason M. Reese

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

Abstract

We present a new coupling approach for the time advancement of multi-physics models of multiscale systems. This extends the method of E et al. (2009) [5] to deal with an arbitrary number of models. Coupling is performed asynchronously, with each model being assigned its own timestep size. This enables accurate long timescale predictions to be made at the computational cost of the short timescale simulation. We propose a method for selecting appropriate timestep sizes based on the degree of scale separation that exists between models. A number of example applications are used for testing and benchmarking, including a comparison with experimental data of a thermally driven rarefied gas flow in a micro capillary. The multiscale simulation results are in very close agreement with the experimental data, but are produced almost 50,000 times faster than from a conventionally-coupled simulation.

Original languageEnglish
Pages (from-to)261-272
Number of pages12
JournalJournal of Computational Physics
Volume284
Early online date24 Dec 2014
DOIs
Publication statusPublished - 1 Mar 2015

Keywords

  • Multiscale simulations
  • Unsteady micro/nano flows
  • Hybrid methods
  • Scale separation
  • Rarefied gas dynamics
  • Gas flows
  • Lotka–Volterra
  • Population dynamics
  • Heterogeneous multiscale method
  • Gas bearings
  • Lubrication
  • Knudsen pump
  • Compressor
  • Coupling
  • Mesoscale

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