Stepped block protection has considerable potential as a low-cost method for the construction of chute spillways and the protection of embankments from erosion by overtopping flow. Stepped spillways are structurally stable, resistant to water loads and significantly increase the rate of energy dissipation on the spillway face thus eliminating or greatly reducing the need for a large energy diss...

In this paper, we use the parallel open source code parallelSPHysics based on the weakly compressible Smoothed Particle Hydrodynamics (WCSPH) approach to study a spillway flow over stepped stairs. SPH is a robust mesh-free particle modelling technique and has great potential in treating the free surfaces in spillway hydraulics. A laboratory experiment is carried out for the different flow disch...

Current weather indifferent fields of science and engineering research purposes and different applications are studied. One of the applications of climate studies, the study of the flow over the weir dam and lower exhaust tunnel is aimed at preventing the risk of cavitations. Aeration is known as one of the most economical and practical way to deal with cavitations on rapid spill ways. In the s...

The Karahnjukar dam spillway is the spillway for the Halslon reservoir, the main reservoir for the 690 MW Karahnjukar Hydroelectric Project in East Iceland. The spillway consist of a 140 m long overflowing weir with a capacity of 2250 m3/s which discharges into a side channel, followed by a 450 m long chute. The chute terminates at a canyon edge where the jet drops some 100 m into a narrow gorg...

The design floods of several reservoirs were recently re-evaluated and the revised spillway outflow could result in dam overtopping with catastrophic consequences for some embankment structures. Herein a physical study was performed on flat and pooled stepped spillways with a slope typical of embankments (θ = 26.6◦) and four stepped configurations were tested: a stepped spillway with flat horiz...

A dam spillway is a hydraulic structure that appropriately and safely diverts the outflow to downstream, so that the dam stability and passing of flood flows can be guaranteed. Compared to straight crest spillway, an Ogee spillway with curvature in plan in a fixed-width can pass more flow. Therefore under the low hydraulic heads and the need for a smaller place in plane, they are considered as ...

In the present study, flow over flat and pooled stepped spillways was simulated three dimensionally. The VOF method and k- ε (RNG) turbulent model was used to simulate the flow over the stepped spillway. The results indicated that the numerical model was acceptably capable of simulating the flow over the pooled and flat stepped spillways for different discharges. Following that, the effect of d...

In traditional models only an order one fraction of energy is transferred from the inflaton to radiation through nonperturbative resonance production in preheating immediately after inflation, due backreaction effects. We propose a particle mechanism that could improve depletion density by up four orders magnitude. The improvement comes fast perturbative decays resonantly produced daughter part...