Multi-physics simulations of large domains with few regions of interest do not require full 3D simulations, but we can instead partition the domain and only simulate regions of interest with 3D models, while simulating the rest with 1D models. preCICE has already been used for 1D-3D fluid-structure interaction simulations of helicopter rotor blades, as well as 2D-3D flow simulations. This thesis focuses on geometric multi-scale fluid-structure interaction simulations via preCICE. In particular this thesis investigates the coupling of 1D and 3D fluid simulations in elastic tubes by comparing different scenarios. To compare different scenarios, this thesis considers single-physics solvers as independent units for 1D and 3D fluid-structure interaction. These independent units are then coupled via a black-box coupling strategy. For this purpose, fluid models are implemented at 3D scale using OpenFOAM and at 1D scale in Nutils and Python. For fluid-structure interaction in elastic tubes, the preCICE tutorials elastic tube 3D and elastic tube 1D are used. As a first step, geometric multi-scale fluid-fluid coupled simulations are implemented and compared with a monolithic 3D simulation. The 1D fluid model shows some inaccuracies which affect the flow behavior in the 3D domain, as the data exchange is bidirectional at the coupling interface. The next step includes coupling combinations of elastic tube 3D and 1D with fluid models to investigate the fluid-fluid-structure scenarios. These combinations include: elastic tube 1D–fluid 3D, elastic tube 3D–fluid 1D and elastic tube 3D–monolithic elastic tube 1D. Overall, most scenarios show a relatively smooth flow profile across the fluid-fluid interface, with some discontinuities and oscillations that are attributed to the dissimilar pressure modeling of the two solvers. Furthermore, the aforementioned last combination related to geometric multi-scale coupling of fluid-structure interaction models involves different physical elastic structures. Hence, the effect of pressure results into discontinuous displacement across the interface of the 3D and the 1D elastic tubes.     «

Multi-physics simulations of large domains with few regions of interest do not require full 3D simulations, but we can instead partition the domain and only simulate regions of interest with 3D models, while simulating the rest with 1D models. preCICE has already been used for 1D-3D fluid-structure interaction simulations of helicopter rotor blades, as well as 2D-3D flow simulations. This thesis focuses on geometric multi-scale fluid-structure interaction simulations via preCICE. In particular t...     »