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Christian Landry

Cette personne a quitté l’EPFL

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Publications associées (36)

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Interaction of a pulsating vortex rope with the local velocity field in a Francis turbine draft tube

François Avellan, Andres Müller, Christian Landry, Matthieu Dreyer, Arthur Tristan Favrel, Steven Roth, Alberto Bullani

Acoustic resonances in Francis turbines often define undesirable limitations to their operating ranges at high load. The knowledge of the mechanisms governing the onset and the sustenance of these instabilities in the swirling flow leaving the runner is es ...

IOP science2013

New insight in Francis turbine cavitation vortex rope: role of the runner outlet flow swirl number

François Avellan, Christophe Nicolet, Arthur Tristan Favrel, Andres Müller, Christian Landry, Joao Gomes Pereira Junior

At part load operation, Francis turbines experience the development of a cavitation vortex rope in the draft tube, whose precession acts as a pressure excitation source. In case of resonance, the resulting pressure pulsations lead to unacceptable torque an ...

Taylor & Francis Ltd2018

Dynamics of the precessing vortex rope and its interaction with the system at Francis turbines part load operating conditions

François Avellan, Arthur Tristan Favrel, Christian Landry, Andres Müller, Keita Yamamoto, Joao Gomes Pereira Junior

At part load conditions, Francis turbines experience the formation of a cavitation vortex rope at the runner outlet whose precession acts as a pressure excitation source for the hydraulic circuit. This can lead to hydro-acoustic resonances characterized by ...

2017

Hydro-acoustic resonance behavior in presence of a precessing vortex rope: observation of a lock-in phenomenon at part load Francis turbine operation

François Avellan, Arthur Tristan Favrel, Andres Müller, Christian Landry, Keita Yamamoto

Francis turbines operating at part load condition experience the development of a cavitating helical vortex rope in the draft tube cone at the runner outlet. The precession movement of this vortex rope induces local convective pressure fluctuations and a s ...

IOP science2014

Hydroelectric System Response to Part Load Vortex Rope Excitation

François Avellan, Christophe Nicolet, Christian Landry, Sébastien Alligné, Joao Gomes Pereira Junior, Antoine Béguin

The prediction of pressure and output power fluctuations amplitudes on Francis turbine prototype is a challenge for hydro-equipment industry since it is subjected to guarantees to ensure smooth and reliable operation of the hydro units. The European FP7 re ...

International Association For Hydraulic Research2016

Transposition of Francis turbine cavitation compliance at partial load to different operating conditions

François Avellan, Arthur Tristan Favrel, Christian Landry, Joao Gomes Pereira Junior

Francis turbines operating in part load conditions experience a swirling flow at the runner outlet leading to the development of a precessing cavitation vortex rope in the draft tube. This cavitation vortex rope changes drastically the velocity of pressure ...

2017

Measurements of Cavitation Compliance in the Draft Tube Cone of a Reduced Scale Francis Turbine Operating at Part Load

François Avellan, Christophe Nicolet, Christian Landry, Arthur Tristan Favrel, Joao Gomes Pereira Junior

Francis turbines operating at part load conditions typically experience a cavitation vortex rope immediately at the runner outlet. As the compliance of this cavitation flow is much higher than the one in cavitation-free conditions, a decrease in the value ...

2018

Experimental Hydro-Mechanical Characterization of Full Load Pressure Surge in Francis Turbines

François Avellan, Arthur Tristan Favrel, Christian Landry, Andres Müller, Keita Yamamoto

Full load pressure surge limits the operating range of hydro-electric generating units by causing significant power output swings and by compromising the safety of the plant. It appears during the off-design operation of hydraulic machines, which is increa ...

2017

Prediction of hydro-acoustic resonances in hydropower plants by a new approach based on the concept of swirl number

François Avellan, Christophe Nicolet, Arthur Tristan Favrel, Christian Landry, Sébastien Alligné, Loïc Andolfatto, Joao Gomes Pereira Junior

Hydropower plant units operating in off-design conditions are subject to cavitation flow instabilities, potentially inducing hydro-acoustic resonances under certain conditions. They can be predicted by using one-dimensional numerical models of hydropower p ...

Taylor & Francis Ltd2019

Dynamic modal analysis during reduced scale model tests of hydraulic turbines for hydro-acoustic characterization of cavitation flows

François Avellan, Arthur Tristan Favrel, Christian Landry, Joao Gomes Pereira Junior

Francis turbines operating at off-design conditions experience the development of unfavourable cavitation flows in the draft tube at the runner outlet, which induce pressure pulsations and hydro-acoustic resonances in the worst cases. The assessment of hyd ...

2019

Flow characteristics and influence associated with inter-blade cavitation vortices at deep part load operations of a Francis turbine

François Avellan, Arthur Tristan Favrel, Christian Landry, Keita Yamamoto

At a deep part load operation, Francis turbines are subject to the formation of inter-blade cavitation vortices inside blade channels, however its characteristics are not fully understood yet. The present study aims to investigate the development of the in ...

2017

Pressure measurements and high speed visualizations of the cavitation phenomena at deep part load condition in a Francis turbine

François Avellan, Andres Müller, Christian Landry, Arthur Tristan Favrel, Keita Yamamoto

In a hydraulic power plant, it is essential to provide a reliable, sustainable and flexible energy supply. In recent years, in order to cover the variations of the renewable electricity production, hydraulic power plants are demanded to operate with more e ...

IOP Publishing2014

Local wave speed and bulk flow viscosity in Francis turbines at part load operation

François Avellan, Christophe Nicolet, Arthur Tristan Favrel, Andres Müller, Christian Landry

The operation of Francis turbines at off-design conditions may cause the development of a cavitation vortex rope in the draft tube cone, acting as a pressure excitation source. The interactions between this excitation source and the hydraulic system at the ...

Taylor & Francis Ltd2016

Analysis of the part load helical vortex rope of a Francis turbine using on-board sensors

François Avellan, Arthur Tristan Favrel, Christian Landry, Keita Yamamoto

The cavitation helical vortex rope arising at Francis turbine partial load induces pressure fluctuations at the rope precession frequency, which can be decomposed into two components; the convective one and the synchronous one. The latter acts as an excita ...

Iop Publishing Ltd2015

Modeling of Unsteady Friction and Viscoelastic Damping in Piping Systems

François Avellan, Andres Müller, Christophe Nicolet, Christian Landry

In real systems, the phenomena, such as pipe-wall viscoelasticity, unsteady friction or fluid structure interaction induce additional damping and dispersion of transient pressure waves than that defined by classical waterhammer. In this paper, unsteady fri ...

International Association For Hydraulic Research2012

Francis turbine draft tube modelling for prediction of pressure fluctuations on prototype

François Avellan, Arthur Tristan Favrel, Christian Landry, Sébastien Alligné

The prediction of pressure fluctuations amplitudes on Francis turbine prototype is a challenge for hydro-equipment industry since it is subjected to guarantees to ensure smooth and reliable operation of the hydro units. The European FP7 research project Hy ...

Iop Publishing Ltd2015