Search

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]

The weakly compressible SPH (WCSPH) method has been widely used for solving hydrodynamic problems, in which the fluid is assumed to be weakly compressible through limiting the density deviation to a small value. Despite its simplicity and robustness in implementation, the WCSPH method is generally hindered by its poor accuracy and spurious oscillations in the pressure field which may lead to numerical instability. In order to dampen the spurious oscillations without introducing excessive dissipation, a Roe-type approximate Riemann solver with a low-dissipation limiter was proposed and applied to the WCSPH method by Zhang et al. (2017). The present paper aims to extend this low-dissipation Riemann solver to the finite particle method (FPM), which can be referred to an enhanced or modified version of the conventional SPH method, for reducing spurious pressure oscillations and meanwhile achieving higher order of accuracy. Numerical results demonstrate that the Riemann solver based FPM is effective in modeling incompressible flows and it produces a more accurate flow field than the conventional WCSPH and Riemann solver based WCSPH methods. [ABSTRACT FROM AUTHOR]