Publication

Forced and Self Oscillations of Hydraulic Systems Induced by Cavitation Vortex Rope of Francis Turbines

Publications associées (30)

Study of flexible operating conditions in variable-speed hydraulic turbines : advanced models and experimental validation

The global imperative to transition from fossil fuel-based energy sources to renewable alternatives has become increasingly urgent in the pursuit of sustainable and renewable power generation. This paradigm shift necessitates innovative approaches to manag ...

EPFL2024

On the prediction of the induced damage by the start-up sequence of Francis turbines: On operational resilience framework

Mario Paolone, Christophe Nicolet, Elena Vagnoni, Martin Seydoux

The number of transient operations in hydraulic machinery connected to power grid, notably start-ups and shut-downs, has observed a substantial increase in recent decades, primarily driven by the global shift toward intermittent renewable energy sources. S ...

Pergamon-Elsevier Science Ltd2024

Adaptive Finite Elements with Large Aspect Ratio. Application to Aluminium Electrolysis

Paride Passelli

The goal of this work is to use anisotropic adaptive finite elements for the numerical simulation of aluminium electrolysis. The anisotropic adaptive criteria are based on a posteriori error estimates derived for simplified problems. First, we consider an ...

EPFL2024

Enhancing Wind Farm Performance through Axial Induction and Tilt Control: Insights from Wind Tunnel Experiments

Fernando Porté Agel, Guillem Armengol Barcos

Static axial induction control and tilt control are two strategies that have the potential to increase power production in wind farms, mitigating wake effects and increasing the available power for downstream turbines. In this study, wind tunnel experiment ...

MDPI2024

Noise-induced transitions past the onset of a steady symmetry-breaking bifurcation: The case of the sudden expansion

François Gallaire, Edouard Boujo, Yves-Marie François Ducimetière

We consider fluid flows, governed by the Navier-Stokes equations, subject to a steady symmetry-breaking bifurcation and forced by a weak noise acting on a slow timescale. By generalizing the multiple-scale weakly nonlinear expansion technique employed in t ...

2024

A cut-cell method for the numerical simulation of 3D multiphase flows with strong interfacial effects

Marco Picasso, Alexandre Caboussat, Julien Hess, Alexandre Masserey

We present a numerical model for the approximation of multiphase flows with free surfaces and strong interfacial effects. The model relies on the multiphase incompressible Navier-Stokes equations, and includes surface tension effects on the interfaces betw ...

Academic Press Inc Elsevier Science2024

Power performance of a model floating wind turbine subjected to cyclic pitch motion: A wind tunnel study

Fernando Porté Agel, Guiyue Duan, Daniele Gattari

Wind tunnel experiments were performed with a miniature floating wind turbine model to study the effects of cyclic pitch motion on its power performance. The cyclic pitch motion was prescribed by two key parameters: pitch frequency and amplitude. The power ...

IOPscience2024

NBI optimization on SMART and implications for scenario development

Mario Ludovico Podesta, Francesca Maria Poli

The SMall Aspect Ratio Tokamak (SMART) under commissioning at the University of Seville, Spain, aims to explore confinement properties and possible advantages in confinement for compact/spherical tokamaks operating at negative vs. positive triangularity. T ...

Iop Publishing Ltd2024

Instability and trajectories of buoyancy-driven annular disks: A numerical study

François Gallaire, Pier Giuseppe Ledda, Giovanni Vagnoli

We investigate the stability of the steady vertical path and the emerging trajectories of a buoyancy -driven annular disk as the diameter of its central hole is varied. The steady and axisymmetric wake associated with the steady vertical path of the disk, ...

Amer Physical Soc2024

Large-scale in-silico analysis of CSF dynamics within the subarachnoid space of the optic nerve

Gilles Fourestey

BackgroundImpaired cerebrospinal fluid (CSF) dynamics is involved in the pathophysiology of neurodegenerative diseases of the central nervous system and the optic nerve (ON), including Alzheimer's and Parkinson's disease, as well as frontotemporal dementia ...

BMC2024