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An improved coupling method of smoothed particle hydrodynamics (SPH) and element bending group (EBG) is developed for modeling the interaction of viscous flows with free surface and flexible structures with free and fixed ends. SPH and EBG are both particle methods which are appealing in modeling problems with free surfaces, moving interfaces and large deformations. SPH is used to model viscous fluid, while EBG is used to model flexible structure. Structure particles are also used as moving boundary for SPH, and the interaction of flexible structure with fluid is therefore modeled through the interaction of structure particles and fluid particles. A fixed-end treatment is introduced for flexible structures. A free surface treatment and a surface tension model are used for free surface flow. The improved SPH–EBG method is applied to simulate problems of dam break flow on flexible structures. The good agreement of presented numerical results with existing experimental and numerical results clearly demonstrates the effectiveness of the SPH and EBG coupling approach in modeling fluid–flexible structure interactions. [ABSTRACT FROM AUTHOR]

Predicting the propagation and transformation of the solitary wave is very important in coastal engineering. This paper presents a numerical investigation of the solitary wave breaking over a slope by using a finite particle method (FPM), which is an enhanced smoothed particle hydrodynamics (SPH). We firstly conduct a comparative study on SPH and FPM in modelling solitary wave and it is demonstrated that FPM performs better than SPH qualitatively and quantitatively. A modified particle shifting technique (PST) is integrated into FPM to avoid possible ill corrective matrix due to extremely disordered particle distribution. We find that the artificial viscous coefficient can greatly influence the wave run-up and propose an empirical equation to quickly determine the optimal value of the artificial viscous coefficient used in the FPM simulations. The solitary wave breaking is then modelled for scenarios with relative wave heights and slopes, and three typical breaking types, including surging breaker (SU), plunging breaker (PL) and spilling breaker (SP), are analyzed. The result indicates that SP affects the pressure field more extensive than PL and SU. When the breaker type transits from SP to SU, the breaker tends to break at a narrower region close to the shoreline, the breaking depth decreases, the breaking index gradually turns into an unstable value, and the relative run-up height of breaking waves becomes larger. Although the wave celerity at breaking has no clear relationship with breaker types, the wave celerity at breaking increases with the increase of the relative wave height and slightly decreases with a steeper slope. • For simulations of the solitary wave breaking over slopes, FPM performs better than SPH in terms of stability and accuracy. • An empirical equation is proposed to decide the artificial viscous coefficient for simulating wave transformation by FPM. • The spilling breaker affects the pressure field more extensive than plunging breaker and surging breaker. • The wave celerity at breaking has no clear relationship with breaker types. • The wave dissipation turns into lower when wave breaking types change from spilling breaker to surging breaker. [ABSTRACT FROM AUTHOR]