A coupled NMM-SPH method for fluid-structure interaction problems

Abstract

• A coupled NMM-SPH method for fluid-structure interaction problems is present. • The proposed method takes full advantage of NMM for the solid structures and SPH for fluid particles. • A contact algorithm is developed which can handle the interaction between NMM elements and SPH particles well. • Compared to DDA-SPH or DEM-SPH, NMM-SPH can accurately calculate the stress of the structure. • The proposed method can also predict the failure of the solid structure under the action of fluid. The main challenges in the numerical simulation of fluid–structure interaction (FSI) problems include the solid fracture, the free surface fluid flow, and the interactions between the solid and the fluid. Aiming to improve the treatment of these issues, a new coupled scheme is developed in this paper. For the solid structure, the Numerical Manifold Method (NMM) is adopted, in which the solid is allowed to change from continuum to discontinuum. The Smoothed Particle Hydrodynamics (SPH) method, which is suitable for free interface flow problem, is used to model the motion of fluids. A contact algorithm is then developed to handle the interaction between NMM elements and SPH particles. Three numerical examples are tested to validate the coupled NMM-SPH method, including the hydrostatic pressure test, dam-break simulation and crack propagation of a gravity dam under hydraulic pressure. Numerical modeling results indicate that the coupled NMM-SPH method can not only simulate the interaction of the solid structure and the fluid as in conventional methods, but also can predict the failure of the solid structure.