UNIGE document Scientific Article
previous document  unige:97527  next document
add to browser collection

Regularized characteristic boundary conditions for the Lattice-Boltzmann methods at high Reynolds number flows

Wissocq, Gauthier
Gourdain, Nicolas
Eyssartier, Alexandre
Published in Journal of Computational Physics. 2017, vol. 331, p. 1-18
Abstract This paper reports the investigations done to adapt the Characteristic Boundary Conditions (CBC) to the Lattice-Boltzmann formalism for high Reynolds number applications. Three CBC formalisms are implemented and tested in an open source LBM code: the baseline local one-dimension inviscid (BL-LODI) approach, its extension including the effects of the transverse terms (CBC-2D) and a local streamline approach in which the problem is reformulated in the incident wave framework (LS-LODI). Then all implementations of the CBC methods are tested for a variety of test cases, ranging from canonical problems (such as 2D plane and spherical waves and 2D vortices) to a 2D NACA profile at high Reynolds number (Re = 10<sup>5</sup>), representative of aeronautic applications. The LS-LODI approach provides the best results for pure acoustics waves (plane and spherical waves). However, it is not well suited to the outflow of a convected vortex for which the CBC-2D associated with a relaxation on density and transverse waves provides the best results. As regards numerical stability, a regularized adaptation is necessary to simulate high Reynolds number flows. The so-called regularized FD (Finite Difference) adaptation, a modified regularized approach where the off-equilibrium part of the stress tensor is computed thanks to a finite difference scheme, is the only tested adaptation that can handle the high Reynolds computation.
Keywords Lattice Boltzmann methodCharacteristic boundary conditionsLODIHigh Reynolds number flows
Full text
Research group Scientific and Parallel Computing
(ISO format)
WISSOCQ, Gauthier et al. Regularized characteristic boundary conditions for the Lattice-Boltzmann methods at high Reynolds number flows. In: Journal of Computational Physics, 2017, vol. 331, p. 1-18. https://archive-ouverte.unige.ch/unige:97527

10 hits

0 download


Deposited on : 2017-10-10

Export document
Format :
Citation style :