Strongly Coupled Fluid-Structure Interaction with Application to Blood Flow in Deformable Arteries

本计画的研究目标是克服目前使用的计算技术的不足，开发具有最小平方公式和算法的谱/hp有限元。 流体和固体的物理相互作用在工程的各个分支中具有实际意义。 例子包括空气动力学结构的颤振、由于爆炸引起的结构变形、海底管道和管道的涡致振动、充气坝、降落伞动力学和通过动脉的血流。 由于流体和固体由不同的方程组描述，因此它们被独立地求解，并且从流体流动方程计算的牵引力被用作结构上的施加力。 由于牵引力引起的结构的几何变化反过来影响流动特性。 当涉及高速流动和/或几何复杂结构时，这种双向耦合可能是显著的。 本研究采用了一个单一的计算框架，允许增强的兼容性和准确性的物理耦合的流体和固体。 流体和固体之间的耦合是强制使用隐式强耦合分区程序。 通过可变形动脉的血流将被用作基准问题，所开发的计算框架有可能改变例如与血液相关的疾病的启动和传播的诊断能力以及航空航天结构设计。 该研究还将修改结构力学和计算方法的一些课程，以包括研究流固相互作用问题的方法，并使学生能够在设计涉及流固耦合的系统时找到应对社会挑战的准确解决方案。

The research objective of this project is to overcome the deficiencies of the currently used computational technologies by developing spectral/hp finite elements with least-squares formulation and algorithms. The physical interaction of fluids and solids is of practical significance in various branches of engineering. Examples include flutter of aerodynamic structures, structural deformation due to explosions, vortex induced vibrations of sub-sea pipelines and risers, inflatable dams, parachute dynamics, and blood flow through arteries. Since fluids and solids are described by different sets of equations, they are solved independently and the tractions calculated from the fluid flow equations is used as applied force on the structure. Geometric changes of the structure due to the tractions in turn influences the flow characteristics. This two-way coupling can be significant when high-speed flows and/or geometrically complex structures are involved. The present study employs a single computational framework that allows for enhanced compatibility and accuracy in the physical coupling of the fluid and solid. The coupling between the fluid and solid is enforced using implicit strongly coupled partitioned procedures. Blood flow through deformable arteries will be used as a benchmark problem.The developed computational framework has the potential to transform, for example, diagnostic capabilities for the initiation and propagation of blood-related diseases, and aerospace structures design. The research will also revamp some of the courses in structural mechanics and computational methods to include approaches to study fluid-solid interaction problems and enable students to find accurate solutions to societal challenges in designing systems involving fluid-solid couplings.