Abstract: This paper presents a parallel high-order method for simulating Vortex-Induced Vibrations (VIV) at very challenging situations, such as vibrations of very closely placed solid objects or a row of multiple objects with large relative displacements. This method works on unstructured triangular/quadrilateral hybrid grids by employing the high-order Spectral Difference (SD) method for spatial discretization. By introducing nonuniform sliding meshes, a computational domain is split into several non-overlapping subdomains, and each subdomain can enclose an object and move freely with respect to its neighbors. The two sides of a sliding interface are coupled through a newly developed nonuniform mortar method. A monolithic approach is adopted to seamlessly couple the fluid and the solid vibration equations. Parallelization strategy is studied and achieved by message passing interface implementation. Through a series of numerical tests, we demonstrate that the present method is high-order accurate for both inviscid and viscous flows; for steady uniform flow, the solver can assure free stream preservation; single cylinder VIV simulation agrees well with previous simulations, which verifies the reliability of the method; mesh deformation can be easily applied even when the deformation of the flow field is complicated, and high parallel efficiency can be achieved at the same time.

Key words: fluid-structure interaction, high-order scheme, spectral difference method, sliding-mesh, vortex-induced vibration, parallel computing