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...

Stepped spillways have become a popular method for handling flood releases. The steps increase significantly the rate of energy dissipation taking place on the spillway face and reduce the size of the required downstream energy dissipation basin. The compatibility of stepped spillways with roller compacted concrete (RCC) and gabion construction techniques results in low additional cost for the ...

Many permanent spillway tunnels of high earth-rock dams are rebuilt from their diversion tunnels. Scour problem is focused because of their high water head and velocity. Energy Approach is a new method to Estimating Scour and is used here to estimate the depth of scour downstream of 1 spillway tunnel of Zipingpu Project. The method is illustrated working fine by comparing its results with data ...

This paper presents a classification of cavitation damage levels on spillway surface. Two important factors influencing cavitation damage have been considered in this study, flow velocity and cavitation index. Based on these factors, five different damage levels from no cavitation damage to major cavitation damage have been determined. The method was applied to data of the Shahid Abbaspour dam ...

Air is transported downstream by the water flow in a free-flow spillway tunnel, resulting high negative pressure, which causes gate vibration and cavitation. In this research work, physical model of tunnel was used to investigate effects surface velocity area residual cross sections on air movements. The results demonstrate that distribution forms an S-shaped curve. As increases or decreases, i...

Many of the quality recreational fishing opportunities in Illinois occur in reservoirs. Fish emigration from reservoirs during periods of overflow is termed “dam” or “spillway escapement.” Escapement can detract from recreational fishing opportunities in the reservoir and can disturb downstream ecosystems by creating an influx of unwanted and/or non-native fish. Previous research on spillway es...

Over the course construction of Tugu Reservoir, it is proposed to build a spillway gate increase its performance as flood control infrastructure. The planning requires calculation design discharge for Reservoir Catchment Area. latest was carried out during in 2010. Therefore, necessary evaluate and recalculate using data. This study aims model Area HEC-HMS software. software able simulate rainf...

The sky-jump spillway is an economical solution to return water rivers, but unsuitable flip bucket design might jeopardize the spillway, dam, or other appurtenant works. Characterizing in advance, during phase, position, size, and shape of erosion basin would be useful ensure that flow returned river a safe way. Also, it for safety assessment throughout exploitation phase when has not yet reach...