Publications associées à Experimental study of velocity fields in rectangular shallow reservoirs

Laterally unconfined neutral or negative buoyancy inflow into a quiescent ambient over sloping bottom

This work studies the nearshore hydrodynamics of a shallow turbulent flow entering a laterally unconfined quiescent ambient with a sloping bottom boundary. Examples of such flow are neutrally buoyant ebb tidal jets and hyperpycnal river plumes entering ope ...

EPFL2023

A Fast Hybrid Pressure-Correction Algorithm for Simulating Incompressible Flows by Projection Methods

Jiannong Fang

To enforce the conservation of mass principle, a pressure Poisson equation arises in the numerical solution of incompressible fluid flow using the pressure-based segregated algorithms such as projection methods. For unsteady flows, the pressure Poisson equ ...

2023

Small-scale dynamo with finite correlation times

Jennifer Waltraud Schober

Fluctuation dynamos occur in most turbulent plasmas in astrophysics and are the prime candidates for amplifying and maintaining cosmic magnetic fields. A few analytical models exist to describe their behavior, but they are based on simplifying assumptions. ...

AMER PHYSICAL SOC2023

Visualization and modelling of dynamic flow in fibrous preforms for liquid composite molding

Helena Luisa Teixido Pedarros

Nowadays, Liquid Composite Molding techniques are often used to manufacture high quality fiber reinforced composite parts at a relatively low cost. These involve an infiltration process, in which a liquid resin is forced to ingress into a dry fibrous porou ...

EPFL2023

Experimental quantification of unsteady leading-edge flow separation

Karen Ann J Mulleners, Julien Dominique Claude Deparday

We propose here a method to experimentally quantify unsteady leading-edge flow separation on aerofoils with finite thickness. The methodology relies on the computation of a leading-edge suction parameter based on measured values of the partial circulation ...

Cambridge University Press2022

Transport across thin membranes: Effective solute flux jump

François Gallaire, Pier Giuseppe Ledda, Giuseppe Antonio Zampogna

A model to describe the transport across membranes of chemical species dissolved in an incompressible flow is developed via homogenization. The asymptotic matching between the microscopic and macroscopic solute concentration fields leads to a solute flux j ...

AIP Publishing2022

Three-Dimensional Numerical Modelling of Al-Salam Storm Water Pumping Station in Saudi Arabia

Azin Amini, Azad Koliji

The Al-Salam Pump Station will be constructed in the framework of Jeddah Storm water Masterplan (JSWM) in Saudi Arabia. The station discharges the incoming flow from the Al-Salam storm tunnel to the Red Sea. Its structure includes a circular deep wet well ...

IAHR2022

Temporal and spatial evolution of cavitating bubbles and coherent structures in a confined submerged jet shear layer

Sebastián Camilo Leguizamón Sarmiento, Yuchuan Wang

Purpose The study aims to display the bubbles' evolution in the shear layer and their relationship with the pressure fluctuations. Furthermore, the coherent structures of the first six modes are extracted, in order to provide insight into their temporal an ...

EMERALD GROUP PUBLISHING LTD2021

Numerical investigation on the volute cutwater for pumps running in turbine mode

Elena Vagnoni, Alessandro Morabito

The hydropower sector has recently raised the interest in pump as turbine (PaT) that can be a valid trade-off between capital cost and performance in micro-scale installations. Nevertheless, the modest efficiency of PaTs often restricts their exploitation. ...

Pergamon-Elsevier Science Ltd2021

Effects of spanwise confinement on stratified shear instabilities

François Gallaire, Yves-Marie François Ducimetière

We consider the influence of transverse confinement on the instability properties of velocity and density distributions reminiscent of those pertaining to exchange flows in stratified inclined ducts, such as the recent experiment of Lefauve et al. [J. Flui ...

2021

An Instrumented High-Speed Rotor with Embedded Telemetry for The Continuous Spatial Pressure Profile Measurement in Gas Lubricated Bearings: A Proof of Concept

Jürg Alexander Schiffmann, Karim Magdi Zakaria Abdelrahman Shalash

Pressure is one of the constitutional quantities governing the flow field in gas lubricated bearings. Knowledge of the pressure is of principal importance in the fundamental understanding of such bearings and for the calibration of reduced order models. Th ...

2020

Multi-well capture zones in strip-shaped aquifers

David Andrew Barry, Setareh Nagheli

Capture zone equations for a multi-well system in strip-shaped confined and unconfined aquifers with and without regional flow are presented. The aquifer is limited by two parallel boundaries that are either no flow (barrier) or inflow (variable head) so t ...

PUBLIC LIBRARY SCIENCE2020

Continuously-fed gravity currents propagating over a finite porous substrate

Anton Schleiss, Mário Jorge Rodrigues Pereira Da Franca, Sara Venuleo

We present the results of laboratory investigations of continuously-fed density currents that propagate first over a smooth horizontal bed and then over a porous substrate of limited length. Inflow discharge, initial excess density, and substrate porositie ...

2019

Mitigating tip vortex cavitation by a flexible trailing thread

Mohamed Farhat, Ali Amini

Tip Vortex Cavitation (TVC) is a major issue in design and operation of axial hydraulic machines. We investigate the capacity of a flexible trailing thread in alleviating TVC by analyzing the flow-induced motion. For this purpose, a nylon thread with three ...

AMER INST PHYSICS2019

An Instrumented High-Speed Rotor With Embedded Telemetry For The Continuous Spatial Pressure Profile Measurement In Gas Lubricated Bearings: A Proof Of Concept

Jürg Alexander Schiffmann, Karim Magdi Zakaria Abdelrahman Shalash

Gas lubricated bearings are capable of supporting high speed rotors with satisfactory load capacities. Pressure is one of the constitutional quantities governing the flow field in gas lubricated bearings. Knowledge of the pressure is of principal importanc ...

Amer Soc Mechanical Engineers2019

On the hysteresis of cavitation incipience and desinence in hydraulic machines

Mohamed Farhat, Martino Reclari, Ali Amini

The omnipresent vortical structures in hydraulic machines are extremely prone to the occurrence of cavitation. It is well known that besides the flow parameters, the incipience, development, and disappearance of cavitation within a vortex is very sensitive ...

IOP PUBLISHING LTD2019

Flow field in a reservoir subject to pumped-storage operation - in situ measurement and numerical modeling

Giovanni De Cesare, Anton Schleiss, Michael Müller

In pumped-storage reservoirs, turbulent kinetic energy input from plant operation can be considerably high. Flow velocities were measured by Acoustic Doppler Current Profilers near the intake/outlet structure to describe flow patterns induced by pumped-sto ...

2018

Innovative measurement techniques for atmospheric turbulence and wind energy

Fernando Carbajo Fuertes

The measurement of different atmospheric flow quantities is of utmost importance for a correct understanding of most atmospheric phenomena. Researchers and industry in the fields of meteorology and wind engineering demand extensive and accurate measurement ...

EPFL2018

Distinctive features of horizontal and vertical velocity profiles in turbidity and saline density currents

Giovanni De Cesare, Sara Venuleo, Shun Nomura, Jumpei Hitomi

The flow field of turbidity current and saline density current in lock-gate flume is measured by the ultra-sound Doppler velocity profiler. The horizontal and vertical velocity and their fluctuations are discussed. ...

2018

Fluid dynamics of flow fields in a disposable 600-mL orbitally shaken bioreactor

Florian Maria Wurm, David Hacker, Dominique Terry Monteil Jr, Likuan Zhu

Orbitally shaken bioreactors (OSRs) are commonly used for the cultivation of mammalian cells in suspension. Here we conducted a three-dimensional computational fluid dynamics (CFD) simulation to characterize the fluid field in the disposable 600-mL orbital ...

Elsevier2018