  Solving Fluid-Structure Interaction (FSI) problems using traditional methods
is a big challenge in the field of numerical simulation. As a powerful
multi-physical field coupled library, preCICE has a bright application prospect
for solving FSI, which supports many open/closed source software and commercial
CFD solvers to solve FSI problems in the form of a black box. However, this
library currently only supports mesh-based coupling schemes. This paper
proposes a critical grid (mesh) as an intermediate medium for the particle
method to connect a bidirectional coupling tool named preCICE. The particle and
critical mesh are used to interpolate the displacement and force so that the
pure Lagrangian Smoothed Particle Hydrodynamic (SPH) method can also solve the
FSI problem. This method is called the particle mesh coupling (PMC) method,
which theoretically solves the mesh mismatch problem based on the particle
method to connect preCICE. In addition, we conduct experiments to verify the
performance of the PMC method, in which the fluid and the structure is
discretized by SPH and the Finite Element Method (FEM), respectively. The
results show that the PMC method given in this paper is effective for solving
FSI problems. Finally, our source code for the SPH fluid adapter is open-source
and available on GitHub for further developing preCICE compatibility with more
meshless methods.
