Further enhancement of the particle shifting technique: Towards better volume conservation and particle distribution in SPH simulations of violent free-surface flows

Three‐dimensional weakly compressible moving particle simulation coupled with geometrically nonlinear shell for hydro‐elastic free‐surface flows

“…One should note that between the instants $$$ \tau $$$ = 2.5 and 5.6, and after $$$ \tau $$$ = 6, approximately, the numerical results are slightly higher than the experimental ones. Such discrepancy, also observed in other particle‐based simulations, 65,73,96,97 can be related to the nonphysical expansion of volume due to the adoption PS techniques, as recently investigated by Jandaguian et al 98 and Lyu and Sun 99 . The adoption of recent enhanced particle collision/shifting models is considered as a future task.…”

A Review of SPH Techniques for Hydrodynamic Simulations of Ocean Energy Devices

“…Notwithstanding, it should be underlined that although the original version of PST and its variants show remarkable ability to cope with several challenging problems, their physical rationality could pose some limitations when being applied to realistic engineering problems. For instance, as reported by the extensive SPH literature (see, e.g., [155,157,158,160]), several versions of PST (see, e.g., [118,156]) could trigger the volume-non-conservation issue in simulating violent free-surface flows with long-term duration. This is caused by the fact that in these PST variants, after being repositioned, the particle positions are still updated according to an unchanged velocity field (i.e., non-Lagrangian transport velocity), which is nonphysical from a rigorous point of view.…”

“…Therefore, the SPH community have been struggling for making PST more physical in different ways, such as integrating the shifting velocity, δv, into the governing equations (see, e.g., [155,158]) and using a fully Arbitrary-Lagrangian-Eulerian (ALE) framework (see, e.g., [148,161]); these variants strongly improve the rationality and interpretability of PSTs through rigorous mathematical considerations, although they require modifying the existing codes to a large extent because of the more complex formalism of the governing equations. In addition to that, there have been simpler measures such as locally deactivating shifting when the fluid suffers from the volume-non-conservation issue [157] or introducing a corrective cohesion force to adaptively compensate the over-expansion/compression [160]. On the whole, as a simple and powerful SPH technique, PSTs should be taken into account for simulating OEDs to improve the accuracy and stability of the simulation.…”

High-accuracy three-dimensional surface detection in smoothed particle hydrodynamics for free-surface flows

“…PST has become a popular technology in recent years for improving the robustness and accuracy of the SPH method [9,20,[28][29][30]. Xu et al [28] first developed the PST.…”

“…In this method, the particles are shifted slightly across streamlines to avoid the extreme bunching and stretching of particles. When the PST is applied to free-surface flows, special treatment of the free-surface particles is required to maintain the kinematic boundary condition [9,10,20,30]. Wang et al [20] proposed an improved PST that enables accurate shifting of particles near the free surface.…”