论文标题
多余时间碰撞模型的旋转对称性
Rotation symmetry of the multiple-relaxation-time collision model
论文作者
论文摘要
在基于Hermite-expansion的多余时间晶格Boltzmann（LB）模型中[Shan＆Chen，Int。 J. Mod。物理。 C，18，635，（2007）]，分别为碰撞期的每个紧张时刻分配了单独的放松时间。在这里，我们指出的是，为了在保留弛豫物理学的旋转对称性的同时，可以将单独的放松时间分配给张量的组件，该张量的组件对应于其SO（3）的不可约表示，但没有任何更细的。通过分解多原子气体LB模型中的第二刻[Nie，Shan＆Chen，Phys。 Rev. E 77，035701，（2008）]，构建了具有脱钩和散装粘度的模型。模型的流体动力方程是通过Chapman-Enskog计算获得的，并通过数值模拟验证。
In the Hermite-expansion-based multiple-relaxation-time lattice Boltzmann (LB) model [Shan & Chen, Int. J. Mod. Phys. C, 18, 635, (2007)], a separate relaxation time is assigned to each of the tensorial moments of the collision term. Here we point out that to allow maximum flexibility while preserving the rotational symmetry of the relaxation physics, separate relaxation times can be assigned to the components of a tensor corresponding to its irreducible representation of SO(3) but not any finer. By decomposing the second moment in the LB model for polyatomic gases [Nie, Shan & Chen, Phys. Rev. E 77, 035701, (2008)], a model with decoupled shear and bulk viscosity is constructed. Hydrodynamic equation of the model is obtained via Chapman-Enskog calculation and verified by numerical simulation.
