A smoothed particle hydrodynamics–peridynamics coupling strategy for modeling fluid–structure interaction problems

Fluid–structure interaction (FSI) is a multiphysics problem with diverse application scenarios ranging from the aeroelasticity of aircraft wings and the structural response of marine platforms, to blood circulation through aortic valves. Solving the FSI problems is challenging, predominantly because of the complex time-variant geometry in the fluid–structure interface. To alleviate the difficulties encountered by the grid-based methods in tracking and meshing the fluid–structure interface involving large deformation and structure failures, in this study, we propose a meshfree framework that couples smoothed particle hydrodynamics (SPH) with peridynamics (PD) for the numerical modeling of FSI problems. This SPH–PD framework involves a four-step partitioned coupling procedure, where the key point is utilizing the SPH moving ghost particles as a medium. An original data transfer scheme is developed based on the partnerships built between the SPH moving ghost particles and the PD particles. The structure failures are incorporated in the PD model by adopting a damage law of maximum bond stretch. The SPH–PD method is validated against existing experimental and numerical data. Through the use of this model, we successfully simulate the low-velocity fluid–structure impact and capture the large deformation with local failures.