On the Use of Improved Radial Basis Functions Methods in Fluid-Structure Interaction Simulations

Abstract

The development of an efficient partitioned FSI coupling scheme is reported in this paper, aimed to facilitate interaction between an open-source CSD software package and an in-house academic CFD code. The coupling procedure is based on Radial Basis Functions (RBFs) interpolation for both information transfer and mesh deformation, entailing no dependence on connectivities, and hence making it applicable to different type or even intersecting grids. However, the method calls for increased computational resources in its initial formulation; to alleviate this deficiency, appropriate acceleration techniques have been incorporated, namely the Partition of Unity (PoU) approach and a surface-point reduction scheme. The PoU approach was adopted in case of data transfer, localizing the interpolation process and therefore reducing the size of the coupling matrix. An alternative approach was applied to improve the efficiency of the mesh deformation procedure, based on the agglomeration of the flow/structure interface nodes used for the RBFs interpolation method. For the demonstration of the proposed scheme a static aeroelastic simulation of a real bridge model, during its construction phase, was performed. The extracted results exhibit its potential to encounter effectively such complicated test cases, in a computationally efficient way.