Thermal lattice Boltzmann flux solver and its application for simulation of incompressible thermal flows
Thermal lattice Boltzmann flux solver and its application for simulation of incompressible thermal flows
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DOI：
10.1016/j.compfluid.2014.02.006
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发表时间：
2014-05
影响因子：
2.8
通讯作者：
Y. Wang;C. Shu;C. Teo
中科院分区：
文献类型：
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作者：
Y. Wang;C. Shu;C. Teo
本文提出了一种热格子Boltzmann通量求解器（TLBFS），用于模拟不可压缩热流。在TLBFS中，热格子玻尔兹曼方法（TLBM）仅用于重建TLBM的局部解，以计算细胞界面处的通量。同时，采用有限体积法求解由热格子Boltzmann方程的Chapman-Enskog分析得到的守恒微分方程，得到了胞心处的宏观流动变量。TLBFS中的物理边界条件可以使用与传统Navier-Stokes（N-S）求解器相同的方式直接实现。本求解器消除了与传统的格子Boltzmann方法，如均匀笛卡尔网格的限制，时间步长和网格间距之间的捆绑，以及分布函数的边界条件的实施相关的约束。TLBFS是通过数值算例进行验证的封闭，包括一个正方形的空腔和一个圆柱形的环，从加热的圆柱混合对流。通过数值验证，TLBFS可以有效地和灵活地应用于解决具有弯曲边界的热流问题。
A thermal lattice Boltzmann flux solver (TLBFS) is developed in this work for simulation of incompressible thermal flows. In TLBFS, the thermal lattice Boltzmann method (TLBM) is only applied to reconstruct the local solution of TLBM for evaluation of fluxes at the cell interface. Meanwhile, the macroscopic flow variables at cell centers are obtained by using the finite volume method to solve conservative differential equations recovered from Chapman–Enskog analysis of thermal lattice Boltzmann equation. The physical boundary conditions in TLBFS can be directly implemented using the same way as in conventional Navier–Stokes (N–S) solvers. The present solver eliminates the constraints associated with conventional lattice Boltzmann method such as limitation to uniform Cartesian mesh, tie-up between the time step and the mesh spacing, as well as implementation of boundary conditions for distribution functions. TLBFS is validated through numerical examples of natural convection in enclosures, including a square cavity and a cylindrical annulus, and mixed convection from a heated cylinder. Through numerical validation, it is shown that TLBFS can be effectively and flexibly applied to solve thermal flow problems with curved boundaries.