Το work with title Using improved radial basis functions methods for fluid-structure coupling and mesh deformation by Strofylas Giorgos, Mazanakis Georgios, Sarakinos Sotirios, Lygidakis Georgios, Nikolos Ioannis is licensed under Creative Commons Attribution 4.0 International
Bibliographic Citation
G. A. Strofylas, G. I. Mazanakis, S. S. Sarakinos, G. N. Lygidakis and I. K. Nikolos, "Using improved radial basis functions methods for fluid-structure coupling and mesh deformation," in 7th European Congress on Computational Methods in Applied Sciences and Engineering, 2016, pp. 1545-1563. doi: 10.7712/100016.1905.9110
https://doi.org/10.7712/100016.1905.9110
In this work the development of a partitioned FSI coupling procedure is reported, aiming to facilitate interaction between an open-source CSD (Computational Structural Dynamics) and an in-house academic CFD (Computational Fluid Dynamics) code. Attention is mainly directed towards the efficient and accurate transfer of predicted displacements, velocities (by CSD) and loads (by CFD). More precisely, spatial coupling is achieved using Radial Basis Functions (RBFs) interpolation, which enables point-based interaction, needing therefore no information for connectivities and, consequently, allowing for the utilization of different type or even intersecting structural and flow grids. Although RBFs method seems to be particularly attractive for both data transfer and mesh deformation, it suffers from a significant drawback; it calls for relatively excessive memory and computation time requirements (in its initial formulation). In case of data transfer the Partition of Unity (PoU) approach is adopted as a remedy of the aforementioned deficiency, which regards the decomposition of the examined problem into several smaller ones, to be solved independently and hence more efficiently. In mesh deformation though, improvement of computational performance is succeeded with a surface point reduction technique, based on the agglomeration of the adjacent boundary nodes, i.e., on the fusion of the RBFs centers. Despite the notable reduction of RBFs base points, the proposed method preserves sufficiently the quality of the initial grid. The proposed algorithm is evaluated against a benchmark (for FSI solvers) test case, considering the analysis of the wind action over a standard tall building model. The obtained numerical results confirm its potential for such simulations, highlighting additionally the radically improved computational performance of data transfer and grid deformation procedures.