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Barrage Hoover

Publications associées (25)

Advances in Spillway Hydraulics: From Theory to Practice

Anton Schleiss, José Pedro Gamito de Saldanha Calado Matos

Over the past decades, significant advances have been achieved in hydraulic structures for dams, namely in water release structures such as spillway weirs, chutes, and energy dissipators. This editorial presents a brief overview of the eleven papers in thi ...

2023

Performance and Design of a Stepped Spillway Aerator

Anton Schleiss, Michael Pfister, Stéphane Christian Olivier Terrier

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

The Land-Water-Energy Nexus of Ruzizi River Dams (Lake Kivu Outflow, African Great Lakes Region): Status, Challenges, and Perspectives

Alfred Johny Wüest

Hydroelectric power (HP) represents the main source of electricity in Africa, including the Democratic Republic of Congo. The demand for new dam construction is high, and major projects are currently progressing through planning and implementation stages. ...

FRONTIERS MEDIA SA2022

Numerical simulations of Pelton turbine flow to predict large head variation influence

François Avellan, Cécile Münch-Alligné, Siamak Alimirzazadeh

In the framework of the new feed-in-tariff system in Switzerland for Small Hydropower Plants (SHP), the aim of the SmallFLEX project, led by HES-SO Valais and performed in collaboration with EPFL, WSL, EAWAG, PVE, and FMV, is to show how SHP can provide wi ...

IOP Publishing2021

Effect of 30-Degree Sloping Smooth and Stepped Chute Approach Flow on the Performance of a Classical Stilling Basin

Anton Schleiss, Michael Pfister, José Pedro Gamito de Saldanha Calado Matos, Ivan Stojnic

Advances in dam construction techniques have significantly increased the number of stepped spillways implemented worldwide. Although stepped chutes provide enhanced energy dissipation along the chute, as compared to smooth chutes, an adequate energy dissip ...

2020

Effect of debris damming on wave-induced hydrodynamic loads against free-standing buildings with openings

Anton Schleiss, Michael Pfister, Davide Wüthrich, Claudia Ylla Arbos

Tsunamis, impulse waves, and dam-break waves are rare but catastrophic events, associated with casualties and damage to infrastructures. An adequate description of these waves is vital to assure human safety and to generate resilient structures. Furthermor ...

2020

Stilling Basin Performance Downstream of Stepped Spillways

Ivan Stojnic

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 ...

EPFL2020

GPU-accelerated numerical analysis of jet interference in a six-jet Pelton turbine using Finite Volume Particle Method

François Avellan, Ebrahim Jahanbakhsh, Audrey Paulette Solange Maertens, Sebastián Camilo Leguizamón Sarmiento, Siamak Alimirzazadeh, Christian Vessaz

The Pelton turbine is an impulse turbine typically installed for high head hydroelectric power plants. For a site with a rated head H and discharge Q, a higher specific speed turbine results in a more compact generating unit with reduced manufacturing cost ...

Pergamon-Elsevier Science Ltd2020

Hydraulic Reconstruction of the 1818 Gietro Glacial Lake Outburst Flood

Christophe Ancey, Eric Bardou, Tomás Alfredo Trewhela Palacios

In the spring of 1818, ice avalanches from the Gietro Glacier created an ice dam, which in turn formed a glacial lake in the Drance Valley (Canton of Valais, Switzerland). Today, its maximum volume is estimated to have been 25x10(6) m(3). Cantonal authorit ...

2019

A Data-Driven Approach Based on Multivariate Copulas for Quantitative Risk Assessment of Concrete Dam

Zhenzhu Meng

Risk assessment of dam's running status is an important part of dam management. A data-driven method based on monitored displacement data has been applied in risk assessment, owing to its easy operation and real-time analysis. However, previous data-driven ...

2019

Hydraulic Jump Downstream of a Stepped Chute: An Experimental Study

Anton Schleiss, Michael Pfister, José Pedro Gamito de Saldanha Calado Matos, Ivan Stojnic

The number of stepped spillways significantly increased in the past decades. Among other reasons, this is due to their energy dissipation potential leading to a reduction of the residual energy at the toe of the spillway. To date, only fragmentary designed ...

2019

Kariba plunge pool rehabilitation

Anton Schleiss, Giovanni De Cesare, Azin Amini, Ivan Stojnic, Claudia Ylla Arbos

The Kariba Dam is a 128 m high arch dam located on the Zambezi River, between Zambia and Zimbabwe. It forms the Kariba lake, with a surface of 5400 km2 and a capacity of 185 km3. In the 20 years following dam construction, heavy rainfalls required frequent ...

2018

Improvement of EIA methods for large reservoirs by using network thinking analysis approach: a case study of Azad dam, Iran

Anton Schleiss, Azin Amini

Dam construction and large reservoir projects are essential for sustainable economic developments especially in developing countries like Iran. Such big projects, could have major social and environmental impacts. At this point, Environmental Impact Assess ...

2018

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

Anton Schleiss, Michael Pfister, José Pedro Gamito de Saldanha Calado Matos, 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

On the Efficiency Alteration Mechanisms Due to Cavitation in Kaplan Turbines

François Avellan, Sebastián Camilo Leguizamón Sarmiento

A transport-equation-based homogeneous cavitation model previously assessed and validated against experimental data is used to investigate and explain the efficiency alteration mechanisms in Kaplan turbines. On the one hand, it is shown that the efficiency ...

2017

Hydraulic performance of stepped spillway aerators and related downstream flow features

Stéphane Christian Olivier Terrier

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 ...

EPFL2016

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

Mohammad Javad Ostad Mirza

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 ...

EPFL2016

Hydraulic scaled model tests for the optimization of approach channel excavation and approach flow conditions of haraz morning glory spillway

Anton Schleiss

Haraz dam under construction is located along Tehran-Amol road, 20 km upstream of the Amol city. A tunnel has been designed to detour the traffic temporarily around the dam site to avoid any closure of the main road. This tunnel will be integrated in the m ...

South African National Committee on Large Dams (SANCOLD)2016

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

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

Numerous stepped spillways were built during the last decades. In particular, a stepped spillway may be integrated economically into the downstream face of a RCC gravity dam, or on valley flanks besides embankment or rockfill dams, where slope changes may ...

2015

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

Anton Schleiss, Michael Pfister, José Pedro Gamito de Saldanha Calado Matos, 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, ...

2015