CFD-DEM coupling with multi-sphere particles and application in predicting dynamic behaviors of drifting boats

To simply predict the motion characteristics of a floating ship on the river and assess the safety in floating, this work developed a multiphase fluid-solid coupling solver based on the Volume of Fluid (VoF) model in open-source code OpenFOAM and multi-sphere DEM model in LIGGGHTS. Benchmarks of non-spherical particles settling in the single-phase and two-phase fluids at different Reynolds numbers were studied. The results show that the solver is relatively accurate and can approximately capture the settlement trajectory of particles under different Reynolds numbers. In application, the drift behaviors of a floating ship with different densities were studied. We introduced the hydrodynamic parameters to characterize the mechanical states and evaluate the stability of the drifting boat. We found that the hull weight has a significant influence on the ship drifting motion. Therefore, ship designers can design the ship according to the proposed model to ensure the safety of drifters.