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arXiv · 0907.1720

Lattice Boltzmann Model for High-Order Nonlinear Partial Differential Equations

Baochang Shi·Hanzhong He·Zhaoli Guo
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Abstract

A general lattice Boltzmann (LB) model is proposed for solving nonlinear partial differential equations with the form $\partial_t ϕ+\sum_{k=1}^{m} α_k \partial_x^k Π_k (ϕ)=0$, where $α_k$ are constant coefficients, and $Π_k (ϕ)$ are the known differential functions of $ϕ$, $1\leq k\leq m \leq 6$. The model can be applied to the common nonlinear evolutionary equations, such as (m)KdV equation, KdV-Burgers equation, K($m,n$) equation, Kuramoto-Sivashinsky equation, and Kawahara equation, etc. Unlike the existing LB models, the correct constraints on moments of equilibrium distribution function in the proposed model are given by choosing suitable \emph{auxiliary-moments}, and how to exactly recover the macroscopic equations through Chapman-Enskog expansion is discussed in this paper. Detailed simulations of these equations are performed, and it is found that the numerical results agree well with the analytical solutions and the numerical solutions reported in previous studies.

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Baochang Shi, Hanzhong He, Zhaoli Guo. 2009-07-10. Lattice Boltzmann Model for High-Order Nonlinear Partial Differential Equations. https://doi.org/10.1103/physreve.97.013304

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