A Lattice-Boltzmann Method for Partially Saturated Computational Cells
A Lattice-Boltzmann Method for Partially Saturated Computational Cells
复制标题
DOI：
10.1142/s0129183198001084
复制
发表时间：
1998-12
影响因子：
1.9
通讯作者：
D. Noble;J. Torczynski
中科院分区：
文献类型：
--
作者：
D. Noble;J. Torczynski
格子玻尔兹曼（LB）方法适用于复杂的，移动的几何形状，其中计算单元部分填充有流体。LB算法被修改以包括取决于被流体饱和的单元的百分比的项。该方法对于不符合网格的悬挂障碍物建模非常有用。另一个应用是模拟通过重建介质的流动，这些介质不容易分割成固体和液体区域。详细的比较与FIDAP模拟结果的周期线的圆柱在一个通道中在非零雷诺数的流动。两个案件进行审查。在第一次模拟中，圆柱体被赋予沿通道轴线沿着的恒定速度，并获得稳态解。然后通过给圆柱一个振荡速度来研究系统的瞬态行为。对于稳定和振荡流，该方法提供了良好的协议与FIDAP模拟结果，即使在靠近圆柱表面的位置。与使用“反弹”条件产生的阶梯式解决方案相比，所提出的条件与光滑FIDAP预测接近一致。计算阻力与建议的条件表现出明显的二次收敛网格细化，而不是线性收敛表现出其他LB边界条件。
The lattice-Boltzmann (LB) method is applied to complex, moving geometries in which computational cells are partially filled with fluid. The LB algorithm is modified to include a term that depends on the percentage of the cell saturated with fluid. The method is useful for modeling suspended obstacles that do not conform to the grid. Another application is to simulations of flow through reconstructed media that are not easily segmented into solid and liquid regions. A detailed comparison is made with FIDAP simulation results for the flow about a periodic line of cylinders in a channel at a non-zero Reynolds number. Two cases are examined. In the first simulation, the cylinders are given a constant velocity along the axis of the channel, and the steady solution is acquired. The transient behavior of the system is then studied by giving the cylinders an oscillatory velocity. For both steady and oscillatory flows, the method provides excellent agreement with FIDAP simulation results, even at locations close to the surface of a cylinder. In contrast to step-like solutions produced using the "bounce-back" condition, the proposed condition gives close agreement with the smooth FIDAP predictions. Computed drag forces with the proposed condition exhibit apparent quadratic convergence with grid refinement rather than the linear convergence exhibited by other LB boundary conditions.