An immersed MMALE material point method for FSI problems with structure fracturing

The fluid–structure-interaction (FSI) modeling is important for both academic studies and engineering applications, but is also one of the grand challenges in the numerical modeling community. The FSI problems with multi-material fluid flow and extreme structure deformation accompanied with fractures and crack growth are less explored areas. In these problems, the interface reconstruction, multi-material advection, interface interaction on the complicated fluid structure interface and potential structure fragmentation must be all taken into account. This paper aims to present an effective monolithic approach of immersed multi-material arbitrary Lagrangian Eulerian material point method (IALEMPM) by immersing the MPM particles in the MMALE grid. In this novel method, the interfaces between the fluid and structure are tracked implicitly by the MPM particles and the interface interactions are implicitly implemented by assembling the nodal force and the nodal momentum from both the solid particles and fluid cells. The consistence time integration scheme, rezoning phase and remapping phase are also established to guarantee the consistence requirements during the whole simulation. Numerical examples, including a shock-obstacle interaction, a blast-plate interaction and a structure fragmentation are studied by using the IALEMPM, and all the numerical results show good agreement with the benchmark and the experiment data, which indicates that the IALEMPM is effective for solving these complicated FSI problems.