Europhys. Lett.
Volume 69, Number 4, February 2005
Page(s) 549 - 555
Section Electromagnetism, optics, acoustics, heat transfer, classical mechanics, and fluid dynamics
Published online 19 January 2005
Europhys. Lett., 69 (4), pp. 549-555 (2005)
DOI: 10.1209/epl/i2004-10393-0

Lattice Boltzmann method at finite Knudsen numbers

F. Toschi1, 2 and S. Succi1

1  Istituto Applicazioni Calcolo, CNR - V.le del Policlinico 137, 00161, Roma, Italy
2  INFM, Sezione di Roma "Tor Vergata" - Via della Ricerca Scientifica 1 I-00133 Roma, Italy

received 17 September 2004; accepted in final form 15 December 2004
published online 19 January 2005

A modified lattice Boltzmann model with a stochastic relaxation mechanism mimicking "virtual" collisions between free-streaming particles and solid walls is introduced. This modified scheme permits to compute plane channel flows in satisfactory agreement with analytical results over a broad spectrum of Knudsen numbers, ranging from the hydrodynamic regime, all the way to quasi-free flow regimes up to $Kn \sim 30$.

47.11.+j - Computational methods in fluid dynamics.
47.15.-x - Laminar flows.
67.40.Hf - Hydrodynamics in specific geometries, flow in narrow channels.

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