Geometrically exact methods for fluid-structure interaction

流固耦合的几何精确方法

基本信息

批准号：
249132206
负责人：
Professor Marek Behr, Ph.D.
金额：
--
依托单位：
Lehrstuhl für Computergestützte Analyse Technischer Systeme (CATS)
依托单位国家：
德国
项目类别：
Research Grants
财政年份：
2014
资助国家：
德国
起止时间：
2013-12-31 至 2019-12-31
项目状态：
已结题

来源：
https://gepris.dfg.de/gepris/projekt/249132206?language=en
关键词：
Geometrically exact methods fluid structure

项目摘要

The methods developed in the proposed project will allow the solution of a class of fluid-structure-interaction problems via practical partitioned methods, which could up to now be solved only with monolithic methods. This can be achieved by guaranteeing that both the fluid and structure sides use an identical boundary description. For this purpose, methods based on Non-Uniform Rational B-Splines (NURBS) are used on both fluid and structural sides and coupled at the interface. Beyond that aspect, the separation of solvers for the fluid and the structure remains possible. Using partitioned approaches allows the integration of existing and specialized single-field solvers into an overall solution system. Unfortunately, different surface discretization in presents a challenge in such solvers. The necessary methods to project physical variables from one side to the other reduce the stability of partitioned approaches compared to more elaborate monolithic approaches. So far this problem has not been addressed satisfactorily. By applying approaches based on NURBS, an exact geometry of the wetted surface on both sides can be guaranteed and the transfer errors can be reduced or eliminated. The proposed concept is inspired by the isogeometric analysis (IGA), which has been gaining popularity in the structural analysis in recent years. Performing the numerical load analysis directly on the geometric formulation used during the design process is the main advantage of this method, and it is used in the suggested project on the structural side. Because the generation of suitable volume discretizations has been achieved in IGA only for relatively simple geometries, its application in fluid mechanics is limited. However, extending conventional methods with a NURBS-based boundary formulation can preserve many advantages of the method. This concept is followed in the NURBS-enhanced Finite-Element Method (NEFEM), which will be used in the proposed project on the fluid side. The project involves the development of the essential transfer methods. One intermediate step is the extension of existing methods while using a conventional method on the other, fluid or structural, side. The advantages of the developed methodology will be demonstrated on academic problems and on real-world applications. Advances in robustness and accuracy are expected by the incorporation of the innovative single-field solvers and by the reduction of errors in the transfer methods at the interface. In addition to the method development, a workshop is planned to support the scientific communication about current state of the art in the field of fluid-structure interaction. During this workshop, groundbreaking methods will be presented and discussed by international experts; the workshop will also provide a platform for young academics.

该项目中开发的方法将允许通过实用的分区方法来解决一类流体-结构相互作用问题，而迄今为止这些问题只能用整体方法来解决。这可以通过保证流体侧和结构侧使用相同的边界描述来实现。为此，在流体侧和结构侧均使用基于非均匀有理 B 样条 (NURBS) 的方法，并在界面处进行耦合。除此之外，流体和结构的求解器分离仍然是可能的。使用分区方法可以将现有的和专用的单场求解器集成到整体解决方案系统中。不幸的是，不同的表面离散化对此类求解器提出了挑战。与更复杂的整体方法相比，将物理变量从一侧投影到另一侧的必要方法降低了分区方法的稳定性。到目前为止，这个问题还没有得到令人满意的解决。通过应用基于 NURBS 的方法，可以保证两侧润湿表面的精确几何形状，并可以减少或消除传递误差。提出的概念受到近年来在结构分析中越来越流行的等几何分析（IGA）的启发。直接对设计过程中使用的几何公式进行数值载荷分析是该方法的主要优点，并且在结构方面的建议项目中使用。由于 IGA 只能针对相对简单的几何形状生成合适的体积离散化，因此其在流体力学中的应用受到限制。然而，使用基于 NURBS 的边界公式扩展传统方法可以保留该方法的许多优点。 NURBS 增强有限元法 (NEFEM) 遵循了这一概念，该方法将用于流体侧的拟议项目。该项目涉及基本传输方法的开发。一个中间步骤是扩展现有方法，同时在流体或结构的另一侧使用传统方法。所开发方法的优势将在学术问题和实际应用中得到证明。通过结合创新的单场求解器以及减少接口传输方法中的误差，预计鲁棒性和准确性将得到提高。除了方法开发之外，还计划举办一次研讨会，以支持有关流固耦合领域当前最新技术水平的科学交流。在本次研讨会上，国际专家将介绍和讨论突破性的方法；该研讨会还将为年轻学者提供一个平台。