Incompressible SPH scour model for movable bed dam break flows

Abstract

In this study an incompressible Smoothed Particle Hydrodynamics (ISPH) approach coupled with the sediment erosion model is developed to investigate the sediment bed scour and grain movement under the dam break flows. Two-phase formulations are used in the ISPH numerical algorithms to examine the free surface and bed evolution profiles, in which the entrained sediments are treated as a different fluid component as compared with the water. The sediment bed erosion model is based on the concept of pick-up flow velocity and the sediment is initiated when the local flow velocity exceeds a critical value. Also, a simple viscosity model is used to correct the fluid viscosity due to the mixing of the sediment materials with water. The proposed model is used to reproduce the sediment erosion and follow-on entrainment process under an instantaneous dam break flow and the results are compared with those from the weakly compressible Moving Particle Semi-implicit (WCMPS) method as well as the experimental data. It has been demonstrated that the two-phase ISPH model performed well with the experimental data. The study shows that the ISPH modelling approach can accurately predict the dynamic sediment scouring process without the need to use empirical sediment transport formulas.

WCSPH with Limiting Viscosity for Modeling Landslide Hazard at the Slopes of Artificial Reservoir

“…The problem is illustrated in Figure 2 showing on the left-hand panel the water and solid bed distribution at the initial time; this demonstrative test represents a modification of an erosional dam break tutorial available in SPHERA v8.0 package [35] and shares some relevant features with similar laboratory tests that have been adopted for numerical model validation, including weakly compressible SPH [57,58] and incompressible SPH [29]. In the performed test, the initial depth of the water column is much greater than the thickness of the bed sediment, resulting in a higher and faster excavation at the wave front, as shown by the representative frames on the right-hand side of Figure 2.…”

“…Furthermore, SPH showed great potential in simulating multiphase problems, including non-cohesive sediment interacting with rapidly varied free-surface water flows with moving interfaces and large displacements: scouring behind seawall due to continuous tsunami overflow [27], impulsive dynamics of submerged non cohesive sediments involving buried explosion [28], scour over movable bed dam break flow [29] and downstream fluvial structures [30], shock wave propagation [31], surge waves generated by deformable landslides [32] and submarine deformable landslides [33]. SPH was successfully applied to the three-dimensional simulation of the Vajont landslide which was assumed to move as rigid body [34].…”

Preface Special Issue “Advances in Numerical Modelling of Hydrodynamics”

“…Developments in numerical methods and computing power continue to grow, to cite just a few (Caviedes-Voullième and , Sanders et al 2010, Dawson et al 2013, Cao et al 2015, George 2011, Smith and Liang 2013, Lacasta et al 2013, Zhou et al 2013, Donat et al 2014, Zanotti et al 2015, Delis et al 2011, Juez et al 2014, Jian et al 2015, Ran et al 2015, Murillo and Garcia-Navarro 2010, Marsooli and Wu 2015, Swartenbroekx et al 2013, Guan et al 2014, Kim et al 2014. This growth has opened-up opportunities to increase the accuracy, robustness and computational complexity of latest simulation models, and to address issues of practical relevance for modelling hydrodynamic processes.…”

Simulations of Local Scour Around a Cylindrical Bridge Pier And a Semicircular Abutment Using Unsteady k-ε Model Combined with σ-Grid

“…Mirmohammad and Ketabdari [23], Ran et al [24] presented the method simulating local scour by SPH model. However, up to now, in the most commercial solvers, the SPH model has not been integrated, limiting the applications.…”