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

Chat with Graph Search

Ask any question about EPFL courses, lectures, exercises, research, news, etc. or try the example questions below.

DISCLAIMER: The Graph Chatbot is not programmed to provide explicit or categorical answers to your questions. Rather, it transforms your questions into API requests that are distributed across the various IT services officially administered by EPFL. Its purpose is solely to collect and recommend relevant references to content that you can explore to help you answer your questions.

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 ...

Climate change is predicted to increase atmospheric vapor pressure deficit, exacerbating soil drought, and thus enhancing tree evaporative demand and mortality. Yet, few studies have addressed the longer-term drought acclimation strategy of trees, particul ...

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 ...

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 ...

We consider on the torus the scaling limit of stochastic 2D (inviscid) fluid dynamics equations with transport noise to deterministic viscous equations. Quantitative estimates on the convergence rates are provided by combining analytic and probabilistic ar ...

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 ...

Extreme weather events are increasing in frequency in recent years due to global climate change. These events damage infrastructure and pose an open challenge to engineers to design more weather-resistant infrastructure. As engineers, we turn to nature fo ...

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 ...

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 ...

We introduce a Lamb-wave medium with tunable propagation velocities, which are controlled by a two-dimensional heating pattern produced by a laser beam. We utilized it to demonstrate that waves in an appropriately designed medium can propagate in the form ...

The thesis is dedicated to the study of two main partial differential equations (PDEs) in fluid dynamics: the Navier-Stokes equations, which describe the motion of incompressible fluids, and the transport equation with divergence-free velocity fields, whic ...

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 ...

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 ...

Fluidic actuation enables movement in a wide range of mechanical systems, from simple laboratory devices to more complex industrial machinery. Fluids are used to generate motion of mechanical pieces. The term "fluids" encompasses two types of technologies: ...

In high energy physics, semiconductor-based sensors are widely used in particle tracking applications. These sensors are typically glued on low-mass cooling substrates, which guarantee the correct thermal management and, at the same time, minimise their in ...

The hydraulic design, computational analysis, and experimental investigations of a high-speed small-scale turbopump for mobile waste heat recovery applications based on organic Rankine cycle systems are presented in this paper. Such applications demand hig ...

This work presents a study of two-phase flow generated inside a rock-flow cell setup. It is characterized by a pipe section filled with fluid (oil in our studies) that is put into oscillation around its mass centre by an electric motor. This type of appara ...

In an attempt to go beyond the conventional laboratory experiments widely reported in literature around the emerging technique of soil bio-cementation, this work addresses key challenges related to its large-scale application. Precisely, a state-of-the-art ...

In the canton of Bern, Switzerland, the “Le Bez” torrent is known for its flash floods, causing sediment and wood debris buildup in Villeret village settled on the alluvial fan. To mitigate this issue, a sediment/wood trap system is being implemented upstr ...

In impermeable media, a hydraulic fracture can continue to expand even without additional fluid injection if its volume exceeds the limiting volume of a hydrostatically loaded radial fracture. This limit depends on the mechanical properties of the surround ...

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

Chat with Graph Search

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

Twenty years of irrigation acclimation is driven by denser canopies and not by plasticity in twig- and needle-level hydraulics in a Pinus sylvestris forest

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

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

Quantitative convergence rates for scaling limit of SPDEs with transport noise

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

Drag reduction of flexible disks through vortex ring manipulation

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

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

Optothermal shaping of lamb waves with square and spiral phase fronts

Anomalous dissipation and other non-smooth phenomena in fluids

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

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

Modeling and analysis of miniaturized magnetorheological valve for fluidic actuation

Interlocking modular microfluidic cooling substrates for future high energy physics experiments

Design, computational and experimental investigation of a small-scale turbopump for organic Rankine cycle systems

Rock-Flow Cell Parameters Evaluation Using Ultrasound Doppler Velocimetry

Addressing the challenges of homogeneity, quality control and waste handling in soil bio-cementation: A large-scale experiment

Enhancing Flood Resilience: Sediment Management in Le Bez Torrent

Three-dimensional buoyant hydraulic fractures: finite volume release