A hybrid method of peridynamic differential operator-based Eulerian particle method–immersed boundary method for fluid–structure interaction

This paper proposes a non-local Eulerian particle method coupling with immersed boundary method (IBM) for fluid–structure interaction (FSI) problems. In the Eulerian particle method, the partial differential forms of governing equations are transformed into integral forms using peridynamic differential operator (PDDO). Symmetric particle distribution is applied in the Eulerian particle method, enhancing the efficiency and stability of the algorithm. By introducing the IBM framework into the original Eulerian particle method, we can obtain a new coupling method, which could solve problems with moving bodies inside fluid and extend the applicability of the Eulerian particle method. The numerical procedure of the proposed hybrid method is detailed. The proposed method is then applied to three benchmark problems: 2D flow around a steady rectangle/moving square and an impulsively started rigid plate inside a rectangular box filled with water. The results capture the flow characteristics of these problems, showing the proposed method's stability and accuracy.