Application of Lattice Boltzmann Models Based on Laguerre Quadratures to Force-driven Flows of Rarefied Gases
نویسندگان
چکیده
The Laguerre Lattice Boltzmann (LLB) models are constructed to exactly recover integrals of the equilibrium distribution function over octants of the momentum space. In the mesoscopic formulation of the Boltzmann equation, such integrals are necessary for the implementation of diffuse reflection boundary conditions. In this paper, we consider two implementations of the force term in the LLB models, which we compare through simulations of the Poiseuille flow for values of the Knudsen number Kn varying from 0.01 through to infinity. We find an excellent agreement with the Chapman–Enskog theory at low values of Kn and with the ballistic regime at infinite Kn.
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