Publications associées à Two-phase flow phenomena in hydraulic turbines and pump-turbines operating in synchronous condenser mode

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

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

Towards an improved understanding of wind turbine wakes in complex terrain

Arslan Salim Dar

In this thesis, we explored the effect of certain terrain-induced flow phenomena on the development of wind turbines sited in complex terrain. A combined experimental and analytical approach is used to study wind turbine wakes in different types of complex ...

EPFL2024

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

Martin Seydoux

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

Wind turbine wake superposition under pressure gradient

Fernando Porté Agel, Arslan Salim Dar

We investigate the effect of pressure gradient on the cumulative wake of multiple turbines in wind tunnel experiments spanning across a range of adverse pressure gradient (APG), zero pressure gradient (ZPG), and favorable pressure gradient (FPG). Compared ...

2024

The effect of nacelle-to-rotor size on the wake of a miniature wind turbine

Fernando Porté Agel, Arslan Salim Dar, Rim Majzoub

Wind tunnel experiments are performed to investigate the effect of nacelle-to-rotor size on the wake of a wind turbine under different Reynolds numbers. Four different turbine configurations are tested, which vary in the rotor diameter and nacelle length a ...

IOP Science2024

DC Power Distribution Networks with Direct Current Transformers

Renan Pillon Barcelos

The shift towards DC power distribution networks, enabled by power electronics technologies, is changing the nature of electrical power systems. Nowadays, DC power distribution networks can effectively support the high penetration of distributed energy res ...

EPFL2024

Unified Harmonic Power-Flow and Stability Analysis of Power Grids with Converter-Interfaced Distributed Energy Resources

Johanna Kristin Maria Becker

Modern power distribution systems are experiencing a large-scale integration of Converter-Interfaced Distributed Energy Resources (CIDERs). Their presence complicates the analysis and mitigation of harmonics, whose creation and propagation may be amplified ...

EPFL2024

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

Christophe Nicolet, Mario Paolone, Martin Seydoux, Elena Vagnoni

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

Optimal blade pitch control for enhanced vertical-axis wind turbine performance

Sébastien Le Fouest, Karen Ann J Mulleners

Vertical-axis wind turbines are great candidates to enable wind power extraction in urban and off-shore applications. Currently, concerns around turbine efficiency and structural integrity limit their industrial deployment. Flow control can mitigate these ...

Nature Research2024

Integrated Wireless Power, Data Communication, and Thermal Sensing System for Autonomous Multisite Brain Implants

Implanted medical devices (IMDs) have been widely developed to support the monitoring and recording of biological data inside the body or brain. Wirelessly powered IMDs, a subset of implantable electronics, have been proposed to eliminate the limitations r ...

EPFL2024

Reversible photo-electrochemical device for solar hydrogen and power generation

Sophia Haussener, Alexandre Dominique M. Cattry, Saurabh Yuvraj Tembhurne, Matthieu Jonin, Mahendra Patel

A reversible photo-electrochemical device operating under concentrated irradiation could offer a stand-alone solution for producing solar fuel (in photo-driven electrolysis mode) and power (in fuel cell mode). This strategy would present the advantage of h ...

2024

Functional-Basis Analysis of Non-Stationary Signals in Modern Power Grids: Theory and Implementation in Embedded Systems

Alexandra Cameron Karpilow

Situational awareness strategies are essential for the reliable and secure operation of the electric power grid which represents critical infrastructure in modern society. With the rise of converter-interfaced renewable generation and the consequent shift ...

EPFL2024

Stability Analysis of Second-Order Harmonic Active Filters for Input-Series/Output- Parallel Solid State Transformers

Drazen Dujic, Tianyu Wei, Andrea Cervone

Solid-State Transformers with Input-Series/Output- Parallel configuration offer a convenient solution for AC/DC power conversion, thanks to their modularity, scalability and flexibility. However, as known, they are affected by a second-order harmonic rippl ...

2024

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

Alexandre Caboussat, Alexandre Masserey, Marco Picasso, Julien Hess

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

Confinement-Controlled Crystallization of Guanine

Esther Amstad, Chuen-Ru Li

Guanine crystals are frequently encountered in nature in the beta-polymorph to create structural colors, to enhance the vision of creatures, and for camouflage. Unfortunately, it is challenging to control the crystallization of guanine in aqueous condition ...

Amer Chemical Soc2024

An improved statistical wake meandering model

Fernando Porté Agel, Corey Dean Markfort, Peter Andreas Brugger

A new statistical wake meandering (SWM) model is proposed that improves on existing models in the literature. Compared to the existing SWM models, the proposed model has a closed description that does not require simulations to create look-up tables while ...

IOP Publishing2024

Design and assessment of an evaporating water-cooled methanation reactor for a SOE-based power-to-methane system

Philippe Aubin

The transition towards clean renewable energy sources, where wind and solar are prone to variation, requires adequate energy storage. Power-to-methane (PtM) systems can be part of the solution. Specifically, solid-oxide-electrolyser (SOE) based PtM systems ...

EPFL2024

Advanced control strategies to exploit the hydropower potential enhancing ancillary services provision to the power system

Francesco Gerini

The European Union's Green Deal aims for a 55% reduction in greenhouse gas emissions by 2030. To reach this goal, a massive integration of Renewable Energy Sources (RES) into the power grid is necessary. As RES become a large part of the electricity genera ...

EPFL2024

Modeling and optimization of PCB coils for inductive power transfer systems

Xiaotong Du

The auxiliary power supply for medium voltage converters requires high insulation capability between the source and the load. Inductive power transfer technology, with an air gap between the primary and secondary coil, offers such high insulation capabilit ...

EPFL2024