An experimental study on the upper part-load elliptical vortex instability in a Francis turbine

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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 ...

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 ...

Light and sound waves can move objects through the transfer of linear or angular momentum, which has led to the development of optical and acoustic tweezers, with applications ranging from biomedical engineering to quantum optics. Although impressive manip ...

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 ...

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 ...

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 ...

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 ...

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 ...

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 ...

According to the International Energy Agency, the global net-zero emissions objective requires the installed wind power capacity to increase 11-fold between 2020 and 2050. The scientific community has recently voiced concerns about the logistic feasibility ...

Hydropower plants play a crucial role in the power system facing ambitious renewable energy targets. Due to their inherent controllability, they are well suited to provide flexibility to the grid. However, an increased flexibility provision leads to a prol ...

In this thesis, the aerodynamic challenges in flapping wing flight are addressed. In particular, the effects of different wing kinematics, flexibilities, and planforms on the the leading edge vortex development and aerodynamic performance are investigated. ...

In this study, wind-tunnel experiments are used to investigate cyclic yaw control as a wake mitigation strategy aiming to improve wind farm power production. The control strategy is applied to a single wind turbine and a wind farm comprising of a column of ...

Vertical-axis wind turbines are excellent candidates to diversify wind energy technology, but their aerodynamic complexity limits industrial deployment. To improve the efficiency and lifespan of vertical-axis wind turbines, we desire data-driven models and ...

Orbital angular momentum (OAM) spectrum diagnosis is a fundamental building block for diverse OAM-based systems. Among others, the simple on-axis interferometric measurement can retrieve the amplitude and phase information of complex OAM spectra in a few s ...

In this thesis, we explore the best practice of simulating the wakes of the turbines under active yaw control (AYC) using large-eddy simulation (LES). In the first study, we validate the blade-element actuator disk model (ADM-BE) for a yawed wind turbine. ...

Accurate predictions of how vortices grow, evolve, and separate from aerodynamic objects are desirable for various applications ranging from autonomous aerial vehicles to wind turbines. Here, we present an experimental characterisation of the formation pro ...

The sustainable development of rechargeable aqueous zinc-ion batteries (RZIBs) is severely limited by the uncontrolled zinc dendritic growth and side reactions on the anode. Herein, a lignocellulose nanofiber (LCNF) separator from waste palm with dual-func ...

It has been observed that achiral nanoparticles, such as flat helices, may be subjected to an optical torque even when illuminated by normally incident linearly polarized light. However, the origin of this fascinating phenomenon has so far remained mostly ...

In the framework of the XFLEX HYDRO H2020 European Project, the pumped-storage power plant of Grand'Maison (France), owned by Electricité De France, focuses on the implementation of the hydraulic short-circuit (HSC) operating mode. This mode increases the ...

An experimental study on the upper part-load elliptical vortex instability in a Francis turbine

Chattez avec Graph Search

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

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

Wave-momentum shaping for moving objects in heterogeneous and dynamic media

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

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

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

Wind turbine wake superposition under pressure gradient

Towards an improved understanding of wind turbine wakes in complex terrain

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

Dynamic stall characterisation and control for vertical-axis wind turbines

Structural impact of the start-up sequence on Pelton turbines lifetime: Analytical prediction and polynomial optimization

The effects of kinematics, flexibility, and planform on the vortex formation and aerodynamic performance of flapping wing flight

A wind tunnel study on cyclic yaw control: Power performance and wake characteristics

Time scales of dynamic stall development on a vertical-axis wind turbine blade

Single-shot Kramers-Kronig complex orbital angular momentum spectrum retrieval

Wind Turbine Wakes in Active Yaw Control: Numerical and Theoretical Studies

Strength and timing of primary and secondary vortices generated by a rotating plate

A water-gating and zinc-sieving lignocellulose nanofiber separator for dendrite-free rechargeable aqueous zinc ion battery

Multipolar Pseudochirality-Induced Optical Torque

CFD simulations of hydraulic short-circuits in junctions, application to the Grand’Maison power plant