A sharp interface Lagrangian-Eulerian method for flexible-body fluid-structure interaction
A sharp interface Lagrangian-Eulerian method for flexible-body fluid-structure interaction
复制标题
柔性体液-结构相互作用的锐界面拉格朗日-欧拉方法
DOI：
10.1016/j.jcp.2023.112174
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发表时间：
2023
影响因子：
4.1
通讯作者：
Griffith, Boyce E.
中科院分区：
文献类型：
--
作者：
Kolahdouz, Ebrahim M.;Wells, David R.;Rossi, Simone;Aycock, Kenneth I.;Craven, Brent A.;Griffith, Boyce E.
本文介绍了一种用于模拟流体-结构相互作用(FSI)的尖锐界面方法，该方法涉及由一般非线性材料模型描述的大范围质量密度比的柔性体。这种新的柔体浸没拉格朗日-欧拉(ILE)格式扩展了我们之前关于将分区和浸入方法集成到刚体FSI的工作。我们的数值方法结合了浸没边界(IB)方法的几何和区域解的灵活性，具有与贴体方法相当的精度，后者可以大幅分解流动和应力，直到流体-结构界面。与许多IB方法不同，我们的ILE格式使用流体和固体子区域的不同动量方程，并采用Dirichlet-Neumann耦合策略，通过简单的界面条件连接流体和固体子问题。与前面的工作一样，我们使用近似拉格朗日乘子力来处理沿流固界面的运动界面条件。这种惩罚方法通过引入流体-结构界面的两种表示形式简化了我们的公式所需的线性求解器，其中一种表示与流体一起移动，另一种表示与结构一起移动，它们由刚性弹簧连接。这种方法还允许使用多速率时间步长，这允许我们对流体子问题和结构子问题使用不同的时间步长。我们的流体求解器依赖于离散表面的浸没界面方法(IIM)来沿复杂的界面施加应力跳跃条件，同时允许使用快速结构网格求解器来求解不可压缩的Navier-Stokes方程。体积结构网格的动力学是用大变形非线性弹性的标准有限元方法通过几乎不可压缩的固体力学公式来确定的。该公式还可以很容易地适应总体积恒定的可压缩结构，并且对于至少部分固体边界不接触不可压缩流体的情况，它可以处理完全可压缩的固体结构。选定的网格收敛研究表明，在体积守恒和两个界面表示的对应位置之间的逐点差异以及结构位移的一阶和二阶收敛中，存在二阶收敛。文中还证明了时间步长格式的二阶收敛。为了评估和验证新算法的稳健性和准确性，将其与计算和实验的FSI基准进行了比较。测试用例包括各种流动条件下的光滑和尖锐几何图形。我们还展示了这种方法的能力，通过应用它来模拟几何逼真的、可变形的血液凝块在下腔静脉过滤器中的传输和捕获。
This paper introduces a sharp-interface approach to simulating fluid-structure interaction (FSI) involving flexible bodies described by general nonlinear material models and across a broad range of mass density ratios. This new flexible-body immersed Lagrangian-Eulerian (ILE) scheme extends our prior work on integrating partitioned and immersed approaches to rigid-body FSI. Our numerical approach incorporates the geometrical and domain solution flexibility of the immersed boundary (IB) method with an accuracy comparable to body-fitted approaches that sharply resolve flows and stresses up to the fluid-structure interface. Unlike many IB methods, our ILE formulation uses distinct momentum equations for the fluid and solid subregions with a Dirichlet-Neumann coupling strategy that connects fluid and solid subproblems through simple interface conditions. As in earlier work, we use approximate Lagrange multiplier forces to treat the kinematic interface conditions along the fluid-structure interface. This penalty approach simplifies the linear solvers needed by our formulation by introducing two representations of the fluid-structure interface, one that moves with the fluid and another that moves with the structure, that are connected by stiff springs. This approach also enables the use of multi-rate time stepping, which allows us to use different time step sizes for the fluid and structure subproblems. Our fluid solver relies on an immersed interface method (IIM) for discrete surfaces to impose stress jump conditions along complex interfaces while enabling the use of fast structured-grid solvers for the incompressible Navier-Stokes equations. The dynamics of the volumetric structural mesh are determined using a standard finite element approach to large-deformation nonlinear elasticity via a nearly incompressible solid mechanics formulation. This formulation also readily accommodates compressible structures with a constant total volume, and it can handle fully compressible solid structures for cases in which at least part of the solid boundary does not contact the incompressible fluid. Selected grid convergence studies demonstrate second-order convergence in volume conservation and in the pointwise discrepancies between corresponding positions of the two interface representations as well as between first and second-order convergence in the structural displacements. The time stepping scheme is also demonstrated to yield second-order convergence. To assess and validate the robustness and accuracy of the new algorithm, comparisons are made with computational and experimental FSI benchmarks. Test cases include both smooth and sharp geometries in various flow conditions. We also demonstrate the capabilities of this methodology by applying it to model the transport and capture of a geometrically realistic, deformable blood clot in an inferior vena cava filter.
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影响因子：
3.7
作者：
Rycroft, Chris H.;Wu, Chen-Hung;Kamrin, Ken
通讯作者：
Kamrin, Ken
基于水平集的浸入界面法求解边界处规定速度的不可压缩粘性流
影响因子：
1.8
作者：
Z. Tan;K. Lim;B. Khoo
通讯作者：
B. Khoo
影响因子：
4.1
作者：
E. M. Kolahdouz;A. Bhalla;L. Scotten;B. Craven;Boyce E. Griffith
通讯作者：
E. M. Kolahdouz;A. Bhalla;L. Scotten;B. Craven;Boyce E. Griffith
DOI：
10.1115/1.4029765
发表时间：
2014
期刊：
arXiv: Computational Physics
影响因子：
--
作者：
B. Valkov;C. Rycroft;K. Kamrin
通讯作者：
K. Kamrin
影响因子：
4.1
作者：
Gil, A. J.;Carreno, A. Arranz;Hassan, O.
通讯作者：
Hassan, O.