Minimization of undesired wave reflections at the boundaries of the computational domain in flow simulations with free surface based on the Navier-Stokes equations

基于纳维-斯托克斯方程的自由表面流动模拟中计算域边界处的不良波反射最小化

基本信息

批准号：
321791315
负责人：
Professor Dr.-Ing. Moustafa Abdel-Maksoud
金额：
--
依托单位：
Institut für Fluiddynamik und Schiffstheorie
依托单位国家：
德国
项目类别：
Research Grants
财政年份：
2017
资助国家：
德国
起止时间：
2016-12-31 至 2021-12-31
项目状态：
已结题

来源：
https://gepris.dfg.de/gepris/projekt/321791315?language=en
关键词：
Minimization undesired wave reflections boundaries

项目摘要

The ability to accurately simulate the propagation of free surface waves and the corresponding fluid-structure-interactions are important topics in computational fluid mechanics, especially in regards to maritime industry and research. The main difficulty in applying RANSE-based simulation techniques is minimizing undesired wave reflections at the boundaries of the computational domain, since such reflections can lead to considerable uncertainties in the simulation results. By introducing source terms into the governing equations within a zone in the vicinity of the domain boundary, outgoing waves can be damped. Another way to reduce wave reflections is to couple the RANSE solver with a second flow solver. In this case, the RANSE solution can be blended to the solution of the other flow solver. Within the current state of knowledge, selecting the optimum source terms is a problem which remains insufficiently investigated. Hence, the main aim of this research project is to develop adaptive approaches for minimizing undesired wave reflections. In this case, the source terms will be adjusted with respect to incoming waves so that they are set to their optimum values at all times during the simulation. The developed approaches will minimize undesired wave reflections and enable prediction of the corresponding uncertainties before starting the simulation. After sufficient validation for 2D and 3D simplified cases, the applicability of the developed methods will be demonstrated for typical three-dimensional maritime flow simulation problems.

准确模拟自由表面波的传播和相应的流体-结构相互作用的能力是计算流体力学的重要课题，特别是在海事工业和研究方面。应用基于 RANSE 的仿真技术的主要困难是最大限度地减少计算域边界处的不需要的波反射，因为此类反射可能会导致仿真结果存在相当大的不确定性。通过将源项引入域边界附近区域内的控制方程中，可以衰减出射波。减少波反射的另一种方法是将 RANSE 求解器与第二个流求解器耦合。在这种情况下，RANSE 解可以与其他流求解器的解混合。在目前的知识水平下，选择最佳源项是一个尚未得到充分研究的问题。因此，该研究项目的主要目的是开发自适应方法来最大限度地减少不需要的波反射。在这种情况下，源项将根据入射波进行调整，以便在模拟过程中始终将它们设置为最佳值。所开发的方法将最大限度地减少不需要的波反射，并能够在开始模拟之前预测相应的不确定性。在对 2D 和 3D 简化案例进行充分验证后，将证明所开发方法对于典型的三维海洋流动模拟问题的适用性。