Coupled DEM‐SPH Method for Interaction between Dilated Polyhedral Particles and Fluid

Abstract

The discrete element method (DEM) and smoothed particle hydrodynamics (SPH) can be adopted to simulate the granular materials and fluid media respectively. The DEM-SPH coupling algorithm can be developed for the dynamic interaction between the two media. When the particle material is simulated by polyhedral element, a fluid-solid coupling interface would lead to the complex geometry between the granular particle and the fluid. The boundary particle method is traditionally used for the fluid-solid interface but with low computational efficiency. In this paper, the dilated polyhedral element is constructed based on Minkowski sum theory, while the contact force between the elements is calculated by Hertzian contact model. Accordingly the dilated polyhedra based DEM is established. The weakly compressible SPH is adopted to simulate the fluid medium, while the interaction on the geometrically complex fluid-solid interface is evaluated with the repulsive force model which can be determined by the contact detection between SPH particles and solid particles in geometry. This method avoids the storage and calculation of a large number of boundary particles, which can be potentially applied for the complex fluid-solid boundary. In order to improve the computational efficiency, a GPU-based parallel algorithm is employed to achieve high performance computation of SPH. The acceleration of the parallel algorithm is evaluated by the cases of dam break. The numerical simulation of the impact of dam break on cubes is implemented. The simulation results are verified with the corresponding experimental and simulation results. Therefore, the rationality and accuracy of the DEM-SPH coupling method for numerical simulation of the interaction between granular materials and fluid media are illustrated. This method is then adopted for the impact of falling rocks on underwater pipeline. The force of water and rocks on the pipeline is analyzed. This method can be further applied for real engineering problems.

Using Discrete Multiphysics Modelling to Assess the Effect of Calcification on Hemodynamic and Mechanical Deformation of Aortic Valve

“…The method, being easy to work with a reasonable degree of accuracy, could be extended to complicated physics without much trouble [27]. The SPH method is gaining popularity in a variety of fields and has a wide range of applications such as multiphase flow [25,28], biomedicals [15,17,19,29], fluid-solid interaction [12,[29][30][31][32][33], and hydrodynamic instability [34,35].…”

Semi‐analytical treatment of spherical solids in smoothed‐particle hydrodynamics fluid simulations

“…However, the lower limit of in (9) ( = 0) has to be changed to some 0 > 0, as visualized in Figure 3. Consequently, the upper limit + 1 in (11), (13) and results (12), (14) has to be changed to…”

“…Unfortunately, the method applies only to a single‐wall boundary element in two dimensions (2D) for which an appropriate curvilinear coordinate system has to be specified a priori and the relevant equations have to be derived on the case‐specific basis. A fairly rigorous fluid‐solid coupling method in the context of granular flow was also introduced by Ji et al 12 but it only applies to piecewise‐planar solids and lacks the robustness and generality of the semi‐analytical formulation.…”

High-resolution fluid–particle interactions: a machine learning approach

“…Furthermore, control of the boundary conditions is also difficult. Among the numerical approaches that allow modelling of fluid-particle interactions, the most significant ones are: lattice-Boltzmann method coupled with the discrete element method (DEM) (Lu & Hsiau 2008;Houlsby 2009;Rycroft, Orpe, & Kudrolli 2009;Hassanpour et al 2011), smoothed particle hydrodynamics (Ji, Chen & Liu 2019;Xu, Dong & Ding 2019;Chen et al 2020) and computational fluid dynamics (CFD-DEM) (Wu et al 2010;Hager et al 2011;Jayasundara et al 2011;Tong et al 2013;Zhao & Shan 2013a;Li, Zhao & Kwan 2020b).…”