A dynamic particle refinement strategy in Smoothed Particle Hydrodynamics for Fluid-Structure Interaction problems

The implementation of dynamic refinement in Smoothed Particle Hydrodynamics (SPH) cannot only describe the physical field more minutely but also decrease the computational cost because of the finer spatial resolution and the locally self-adaptive refinement. However, there are several challenges to realize the dynamic refinement in SPH to achieve improved performance. Based on these challenges, this paper provides a general dynamic refinement strategy, and a new refinement criterion involving two-phase materials is proposed to capture the interface more precisely in Fluid-Structure Interaction (FSI) problems. To prove the validity of the strategy, three different models for SPH simulations, including the dynamic refinement model, no refinement model and total refinement model, are designed for a case of water entry of a wedge. By measuring the energy, acceleration and surface pressure of the wedge and comparing the computational cost, the results indicate that this strategy can obtain better accuracy and efficiency, which demonstrates high potential for extension of SPH application to FSI problems. Meanwhile, the new refinement criterion is proven to be more effective than other single-phase refinement criteria. (C) 2018 Elsevier Ltd. All rights reserved.