Numerical simulation of landslide on non-rigid slopes by an explicit three-step incompressible smoothed particle hydrodynamic

The coastal waves caused by landslide in the lake of reservoir dams can threaten the safety of the dam. Therefore, the exact recognition of hydraulic flow due to coastal waves has always been of interest to researchers. So far, extensive laboratory and numerical research has been devoted to it. Also, the phenomenon of landslide in the lake of dams and rivers, and the production and propagation of waves resulting from it, is one of the most important and complex issues in the field of hydraulic engineering. Today, the expansion of numerical relations and the modeling process have somewhat contributed to a rational understanding of these phenomena. In this research, a Lagrangian method is used for solving governing equations. Initially, the hydrodynamic method is defined as an explicit three-step incompressible smoothed particle hydrodynamic. This method, by replacing the fluid with a set of particles, provides an approximate solution to the fluid dynamics equations. In this simulation, there are a series of arbitrary interpolation points that can be assumed to be fluid particles. All variables are calculated by these points and are calculated by an interpolation function. In order to validate the method, the dam break problem on dry bed and the subsurface landslide problem have been used. In the first issue, the correlation coefficient of 0.9998, the mean absolute error of 0.5426 and the efficiency coefficient of the Nash-Sutcliff model 0.974 for the calculated parameters indicate that the model is accurately calibrated, which demonstrates the high capability of this method in simulating free surface fluids and wave-related phenomena. Also, comparing the measured results with the experimental data in the sub-surface landslide simulation showed that the correlation and mean square error correlation coefficients were 0.95 and 0.0071 respectively, which indicates the high accuracy of the model in calculating the water surface profile caused by landslide subsurface. The results showed that at times after 2 seconds, numerical waves tended to release more than its experimental state, with a difference between the ranges of 5 to 10 cm. This is due to the turbulence of the free surface of water causing the flow of complexity. For smaller body weights and deeper depths of submergence, these differences will be lower in scope.
Then three landslide modeling scenarios were designed and implemented. In this study, slopes and non-rigid bodies were considered as a rheological material (pseudoplastic fluid) and entered into modeling as Carreau Yasuda non-Newtonian fluid. The results were reported at 0.3 and 0.6 seconds, and then they were analyzed.
The innovation aspect of this research is that the study of non-rigid slopes during landslide and falling and sliding of non-rigid bodies on them, as well as the production and propagation of waves from it, have not been investigated so far. The purpose of this paper is simulation and review it by an explicit three-step incompressible smoothed particle hydrodynamic. On the other hand, the choice of non-Newtonian Carreau Yasuda fluid to simulate the slope and non-rigid body is another aspect of the innovation of the present study.