An immersed interface-lattice Boltzmann method for fluid-structure interaction
An immersed interface-lattice Boltzmann method for fluid-structure interaction
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DOI：
10.1016/j.jcp.2020.109807
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发表时间：
2020-03
期刊：
影响因子：
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通讯作者：
J. Qin;E. M. Kolahdouz;Boyce E. Griffith
中科院分区：
文献类型：
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作者：
J. Qin;E. M. Kolahdouz;Boyce E. Griffith
提出了一种用于流固耦合系统建模的浸没界面格子Boltzmann方法。这种方法的关键要素是确定的跳跃条件，所满足的分布函数的格子玻尔兹曼方法的框架内施加的力沿着浸没在不可压缩流体的表面。在这个初始的II-LBM中，界面力的法向分量相关的不连续性通过使用类似于在不可压缩Navier-Stokes方程中施加相应的压力不连续性的方法施加相关的跳跃条件来急剧解决。我们发现，跳跃条件的分布函数是相同的单弛豫时间和多弛豫时间LBM配方。切向力的处理使用浸没边界格子玻尔兹曼方法（IB-LBM）。在我们的实现中，水平集方法是用来施加跳跃条件的刚体模型。对于柔性边界模型，我们通过插值随流体运动的标记点的位置来描述运动界面。本文介绍的II-LBM相比，直接强制IB-LBM的刚体流体-结构相互作用，和一个经典的IB-LBM的情况下，涉及弹性界面。高阶精度观察与II-LBM相比，IB-LBM为选定的基准问题。虽然我们的II-LBM只施加跳跃条件对应的压力，在速度场的误差被证明是小得多的II-LBM比IB-LBM。II-LBM也被证明提供上级体积守恒模拟灵活的边界时。
An immersed interface-lattice Boltzmann method (II-LBM) is developed for modeling fluid-structure systems. The key element of this approach is the determination of the jump conditions that are satisfied by the distribution functions within the framework of the lattice Boltzmann method where forces are imposed along a surface immersed in an incompressible fluid. In this initial II-LBM, the discontinuity related to the normal component of the interfacial force is sharply resolved by imposing the relevant jump conditions using an approach that is analogous to imposing the corresponding pressure discontinuity in the incompressible Navier-Stokes equations. We show that the jump conditions for the distribution functions are the same in both single-relaxation-time and multi-relaxation-time LBM formulations. Tangential forces are treated using the immersed boundary-lattice Boltzmann method (IB-LBM). In our implementation, a level set approach is used to impose jump conditions for rigid-body models. For flexible boundary models, we describe the moving interface by interpolating the positions of marker points that move with the fluid. The II-LBM introduced herein is compared to a direct forcing IB-LBM for rigid-body fluid-structure interaction, and a classical IB-LBM for cases involving elastic interfaces. Higher order accuracy is observed with the II-LBM as compared to the IB-LBM for selected benchmark problems. Although our II-LBM only imposes jump conditions corresponding to the pressure, the error in the velocity field is demonstrated to be much smaller for the II-LBM than the IB-LBM. The II-LBM is also demonstrated to provide superior volume conservation when simulating flexible boundaries.