Enhanced-Discretization Interface-Capturing Technique (EDICT) for computation of unsteady flows with interfaces
Enhanced-Discretization Interface-Capturing Technique (EDICT) for computation of unsteady flows with interfaces
复制标题
用于计算具有界面的非定常流的增强型离散化界面捕获技术 (EDICT)
DOI：
10.1016/s0045-7825(97)00194-1
复制
发表时间：
1998
影响因子：
7.2
通讯作者：
M. Behr
中科院分区：
文献类型：
--
作者：
T. Tezduyar;S. Aliabadi;M. Behr
提出了一种用于计算含界面的非定常流动问题的增强型离散化界面捕捉技术(EDICT)，包括双流体和自由面流动。在法令中，我们在一个固定的网格上求解了Navier-Stokes方程和一个控制界面函数演化的平流方程，两个不同的值标识了这两种流体。这些方程空间离散的起点是具有良好稳定性和精度的稳定化有限元格式。为了提高模拟界面的精度，我们使用了与界面及其附近的增强离散化相对应的有限元函数。这些函数设计为具有多个组件，每个组件来自同一计算域上不同级别的网格细化。速度和压力函数的主要组成部分来自称为Mesh-1的基本网格。Mesh-1中的元素的子集被识别为位于或靠近界面，并且根据界面的位置，该子集可以从一个时间层改变到另一个时间层。通过将在该单元子集上生成的第二级网格拼接在一起来构造Mesh-2，速度和压力函数的第二分量来自Mesh-2。对于接口函数，我们有来自Mesh-3的第三个组件，该组件是通过将在Mesh-2中的元素子集上生成的第三级网格拼接在一起而构建的。通过对试验问题的并行计算，我们证明了该法令可以非常有效地用于提高基本有限元公式的精度。
We present the Enhanced-Discretization Interface-Capturing Technique (EDICT) for computation of unsteady flow problems with interfaces, such as two-fluid and free-surface flows. In EDICT, we solve, over a non-moving mesh, the Navier-Stokes equations together with an advection equation governing the evolution of an interface function with two distinct values identifying the two fluids. The starting point for the spatial discretization of these equations are the stabilized finite element formulations which possess good stability and accuracy properties. To increase the accuracy in modeling the interfaces, we use finite element functions corresponding to enhanced discretization at and near the interface. These functions are designed to have multiple components, with each component coming from a different level of mesh refinement over the same computational domain. The primary component of the functions for velocity and pressure comes from the base mesh called Mesh-1. A subset of the elements in Mesh-1 are identified to be at or near the interface, and depending on where the interface is, this subset could change from one time level to another. A Mesh-2 is constructed by patching together the second-level meshes generated over this subset of elements, and the second component of the functions for velocity and pressure comes from Mesh-2. For the interface function, we have a third component coming from a Mesh-3 which is constructed by patching together the third-level meshes generated over a subset of elements in Mesh-2. With parallel computation of the test problems presented here, we demonstrate that the EDICT can be used very effectively to increase the accuracy of the base finite element formulations.