• A CFD model to predict aeration of spillway flow. Highly economical approach combining VOF with explicit modelling air entrainment. Tested at four different step Froude numbers and validated by experimental data. Model implemented within the framework OpenFOAM. This work considers application entrainment developed in [P. Lopes et al. Int. J. Nonlin. Sci. Num., vol. 18, pp. 559-574, 2017] simu...

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 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...

Ogee spillway is the most important structure used to get rid of excess water during flood. Scouring phenomenon occurring in downstream region due high energy dissapation an envitable. This study aims reduce amount scour occurred at stilling basin ogee by using three dissipation blocks namely as baffle, triangle and stepped blocks. A new distribution was proposed for each type dissipated block,...

High-velocity free-surface flows are complex two-phase flows and limited information is available about the interactions between air and water for void fractions of about 50%. Herein a detailed experimental study was conducted in the intermediate flow region ( C ∼ 50%) on a stepped spillway and the microscopic air–water flow characteristics were investigated. The results showed differences in w...