Publication

Air Entrainment in Skimming Flow on Stepped Spillways: the Effect of an Abrupt Slope Change

Publications associées (10)

Performance and Design of a Stepped Spillway Aerator

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Stepped spillways are frequently limited to specific discharges under around 30 m2/s due to concerns about potential cavitation damages. A small air concentration can prevent such damages and the design of bottom aerators is well established for smooth chu ...

2022

Stilling Basin Performance Downstream of Stepped Spillways

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Advances in dam construction techniques have significantly increased the number of implemented stepped spillways worldwide. A key hydraulic feature of a stepped chute, compared to a smooth chute, is the enhanced energy dissipation resulting in a reduced re ...

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Effect of an abrupt slope change on air entrainment and flow depths at stepped spillways

Anton Schleiss, José Pedro Gamito de Saldanha Calado Matos, Michael Pfister, Mohammad Javad Ostad Mirza

Several stepped spillways have been built in recent decades, mostly integrated in the downstream faces of roller compacted concrete dams. Among them, only a few have changing bottom slopes. Comprehensive information on the effect of a slope change on the f ...

Taylor & Francis Ltd2017

Hydraulic performance of stepped spillway aerators and related downstream flow features

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To protect spillways against cavitation damage, adding a small air concentration to the flow close to the invert is efficient. Aerator performance on smooth chutes was therefore well studied in terms of air entrainment and downstream air concentration deve ...

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Experimental study on the influence of abrupt slope changes on flow characteristics over stepped spillways

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Application of stepped spillways increases the energy dissipation rate along the spillway and may reduce the dimensions of the terminal energy dissipation structure. This pronounced energy dissipation makes stepped chutes attractive under various condition ...

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We develop several critical concepts that should be considered when interpreting, modelling and designing future experiments for flows over sloping terrain. Vertical buoyancy fluxes in katabatic flows can be positive and a source of turbulent kinetic energ ...

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Air entrainment and pressure development in skimming flow on an abrupt slope change on stepped spillways

Anton Schleiss, José Pedro Gamito de Saldanha Calado Matos, Michael Pfister, Mohammad Javad Ostad Mirza

Numerous stepped spillways were built to date, namely on RCC gravity dams or on valley flanks besides embankment or rockfill dams, while some others are currently under design or construction. In some cases, slope changes may be required on stepped chutes, ...

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Modeling the Onset of Shallow Landslides in Partially Saturated Slopes Subjected to Rain Infiltration

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Heavy rainfall can lead to shallow slips on slopes which are often initially in a state of partial water saturation. A multiphysics approach and advanced constitutive modeling are necessary to take into account the physical key processes in partially satur ...

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Half-scale experimental study of rockfall impacts on sandy slopes

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In the framework of rockfall trajectory modelling, the bouncing phenomenon occurring when a rock block impacts with the slope surface is the most difficult to predict, owing to its complexity and its very limited understanding. To date, the rebound is comm ...

2009

High velocity aerated flow on stepped chutes with macro-roughness elements

Stéphanie Joëlle André

Uncontrolled overtopping during flood events can endanger embankment dams. Erosion of the downstream slope and scouring of its base caused by the high velocity and energy of the overflow can indeed lead to breach formation until complete failure. In this c ...

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