Computational Modelling of Fluid-Solid Interaction Problems by Coupling Smoothed Particles Hydrodynamics and the Discrete Element Method

Discrete Element Method (DEM) and Smoothed Particles Hydrodynamics (SPH) are integrated to investigate the macroscopic dynamics of fluid-solid interaction (FSI) problems. This coupled model is originated from two different meshless methods without mesh generation, which can handle fluid-particle-structure interactions with structural deformation/failure. With SPH the fluid phase is represented by a set of SPH particle elements moving in accordance with the Navier-Stokes equations. The solid phase consists of single or multiple solid particle(s) phase and deformable structure(s) phase which are represented by DEM particle elements using a linear contact model and a linear parallel contact model to account for the interaction between particle elements, respectively. To couple the fluid phase and solid particle phase, a local volume fraction and a weighted average algorithm are proposed to reformulate the governing equations and the interaction forces. The structure phase is coupled with the fluid phase by incorporating the structure’s DEM particle elements in SPH algorithm. The interaction forces between the solid particles and the structure phases are computed using the linear contact model in DEM. The proposed model is capable of simulating simultaneously fluid-structure interaction, particleparticle interaction and fluid-particle interaction, with good agreement between complicated hybrid numerical methods and experimental results being achieved. Finally, two engineering problems in injection moulding and 3D printing process are carried out to demonstrate the capability of the integrated particle model for simulating fluid-solid interaction problems with the occurrence of structural failure