The paper presents a study of a failure of a dam located at Kolarjevvrh, Slovenia. In case of such an event, water would rush with very high velocity through a steep valley with 10-30% slope to the plain 700 m below. The surge front and free surface in such conditions are difficult to simulate with conventional numerical schemes. The meshless Smoothed Particle Hydrodynamics (SPH) method provides a good alternative. However, the treatmentof boundaries is not straightforward in SPH, and friction plays a significant role in the analysed case. Žagar et al. (2009) modelled the roughness by adding random elevation differences to the surface geometry. In this study, a variable roughness parameter was introduced to the SPH model instead. Both solutions showed good results with slight variances. A comparison between the two approaches is presented, as well as a comparison toa curvilinear finite volume model and measurements on a physical model.
COBISS.SI-ID: 5505633
This paper presents numerical simulations of dam-break flow in channel expansion using the SPH method. Smoothed particle hydrodynamics (SPH) is a meshless method for simulation of hydrodynamics phenomena. The SPH method requires larger number of computational elements and consequently a longer computational time. Therefore, the new methodologies have been developed (for example: coupling between models of different resolutions). It was demonstrated that the proposed approach significantly shortens the computational time of the SPH simulations without decreasing the accuracy of results.
COBISS.SI-ID: 5990753
Smoothed particle hydrodynamics (SPH) is a particle-based Lagrangian method that can be adapted for simulating free surface flows. The method is particularly suitable for phenomena in which the flow changes rapidly. A weakness of the SPH method is the very long computational time. However, this can be significantly reduced using new techniques. In this research, the two-dimensional (2-D) and three-dimensional (3-D) models Tis Isat, developed at the University of Ljubljana, were used with an appropriate coupling procedure. The new model was validatedand calibrated against the results of laboratory experiments. The simulation results of the 2-D/3-D coupled model were compared to themeasurements, to the results of the fully 3-D Tis Isat model and to the results of a one-dimensional (1-D) finite difference (FD) model. The performed SPH simulations showed good agreement with measurements and the 1-D model results in the symmetry axis of the channel. The two greatest advantages of the coupled model are a more realistic description of the water-level below the expansion and the significantly shorter computational time as a result of the adopted coupling procedure.
COBISS.SI-ID: 6269025
The paper describes two different ways of defining the terrain roughness in smoothed particle hydrodynamics (SPH) simulations performed with the Tis Isat model, developed at the University of Ljubljana. The model introduces into the SPH method a nondiscrete boundary condition with friction. Two basic definitions of terrain roughness are used: (a) as a hydraulically smooth wall, where roughness was controlled by the wall–particle eddy viscosity coefficient; and (b) as a hydraulically rough terrain by elevating the meshnodes. The undertaken SPH simulations relate to a dam break at the upper storage reservoir of the pumpedstorage hydro power plant Kolarjev vrh in Slovenia. For the first time, such study was performed on a real topography. Water depths at the gauges along the valley were compared with measurements on a physical model and to results obtained using a finite volume (FV) model. The comparison showed satisfactory agreement with the measurements, which are comparable with the FV model simulations.
COBISS.SI-ID: 6616417
Results of the sediment transport simulations are presented in this paper. In this study the SPH model Tis Isat was used. SPH (Smoothed Particle Hydrodynamics) is still a relatively new numerical method and is being increasingly used in simulations of fluid motion and sediment transport. The presented results of the Tis Isat model were compared to numerical results of another Lagrangian model and to the measurements. The results of the Tis Isat model showed good agreement with measurements.
COBISS.SI-ID: 6809441