Lattice Boltzmann simulation of rarefied gas flows in microchannels
Zhang, Yonghao and Qin, Rongshan and Emerson, David (2005) Lattice Boltzmann simulation of rarefied gas flows in microchannels. Physical Review E: Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics, 71 (4). 047702. ISSN 2470-0053 (https://doi.org/10.1103/PhysRevE.71.047702)
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Abstract
For gas flows in microchannels, slip motion at the solid surface can occur even if the Mach number is negligibly small. Since the Knudsen number of the gas flow in a long microchannel can vary widely and the Navier-Stokes equations are not valid for Knudsen numbers beyond 0.1, an alternative method that can be applicable to continuum, slip and transition flow regimes is highly desirable. The lattice Boltzmann equation (LBE) approach has recently been expected to have such potential. However, some hurdles need to be overcome before it can be applied to simulate rarefied gas flows. The first major hurdle is to accurately model the gas molecule and wall surface interactions. In addition, the Knudsen number needs to be clearly defined in terms of LBE properties to ensure that the LBE simulation results can be checked against experimental measurements and other simulation results. In this paper, the Maxwellian scattering kernel is adopted to address the gas molecule and surface interactions with an accommodation coefficient (in addition to the Knudsen number) controlling the amount of slip motion. The Knudsen number is derived consistently with the macroscopic property based definition. The simulation results of the present LBE model are in quantitative agreement with the established theory in the slip flow regime. In the transition flow regime, the model captures the Knudsen minimum phenomenon qualitatively. Therefore, the LBE can be a competitive method for simulation of rarefied gas flows in microdevices.
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Item type: Article ID code: 5076 Dates: DateEvent5 April 2005PublishedNotes: Also presented at 51st IUVSTA Workshop on Modern Problems and Capability of Vacuum Gas Dynamics, Värmdö, Sweden, July 2007 Subjects: Technology > Mechanical engineering and machinery
Science > PhysicsDepartment: Faculty of Engineering > Mechanical and Aerospace Engineering Depositing user: Strathprints Administrator Date deposited: 07 Jan 2008 Last modified: 18 Aug 2024 00:56 URI: https://strathprints.strath.ac.uk/id/eprint/5076