Publications associées à Inertie

The long cross-over dynamics of capillary imbibition

Spontaneous capillary imbibition is a classical problem in interfacial fluid dynamics with a broad range of applications, from microfluidics to agriculture. Here we study the duration of the cross-over between an initial linear growth of the imbibition fro ...

Cambridge University Press2022

Pseudomomentum: origins and consequences

Harmeet Singh

The balance of pseudomomentum is discussed and applied to simple elasticity, ideal fluids, and the mechanics of inextensible rods and sheets. A general framework is presented in which the simultaneous variation of an action with respect to position, time, ...

2021

An Ink–and–Paper Automaton: The Conceptual Mechanization of Cognition and the Practical Automation of Reasoning in Leibniz’s De Affectibus (1679)

Simon François Dumas Primbault

On ten loose handwritten folios dating back from April 1679, Leibniz gradually devised, in the course of three days, a full-blown theory of thought that nonetheless remained unpublished and still has received little attention from scholars. Conceiving of a ...

2020

Inertia location and slow network modes determine disturbance propagation in large-scale power grids

Philippe René Joseph Jacquod, Laurent Vincent Pagnier

Conventional generators in power grids are steadily substituted with new renewable sources of electric power. The latter are connected to the grid via inverters and as such have little, if any rotational inertia. The resulting reduction of total inertia ra ...

2019

Optimal Placement of Inertia and Primary Control: A Matrix Perturbation Theory Approach

Philippe René Joseph Jacquod

The increasing penetration of new renewable sources of electrical energy reduces the overall mechanical inertia available in power grids. This raises a number of issues regarding grid stability over short to medium time scales. A number of approaches have ...

2019

Noise-induced desynchronization and stochastic escape from equilibrium in complex networks

Melvyn Sandy Tyloo, Robin Delabays

Complex physical systems are unavoidably subjected to external environments not accounted for in the set of differential equations that models them. The resulting perturbations are standardly represented by noise terms. If these terms are large enough, the ...

2019

Translational and Rotational Motion of C8 Aromatics Adsorbed in Isotropic Porous Media (MOF-5): NMR Studies and MD Simulations

Berend Smit, Seyedmohamad Moosavi, Efrem Daniel Braun, Sudabeh Jawahery, Sondre Kvalvag Schnell

We combined nuclear magnetic resonance (NMR) and molecular dynamics (MD) simulation to study xylene behavior in MOF-5, probing the effects of adsorbate geometry in a weakly interacting model isotropic metal organic framework (MOF) system. We employed NMR d ...

American Chemical Society2017

Field-like interactions between motion-based reference frames

Michael Herzog

A reference frame is required to specify how motion is perceived. For example, the motion of part of an object is usually perceived relative to the motion of the object itself. Johansson (Psychological Research, 38, 379-393, 1976) proposed that the percept ...

Springer2015

Accounting for inertia effects to access the high-frequency microrheology of viscoelastic fluids

László Forró, Sylvia Jeney, Elena Bertseva, Frank Scheffold

We study the Brownian motion of microbeads immersed in water and in a viscoelastic wormlike micelles solution by optical trapping interferometry and diffusing wave spectroscopy. Through the mean-square displacement obtained from both techniques, we deduce ...

Amer Physical Soc2014

Modeling and control of large salient-pole synchronous hydro generators and stability issues in isolated production mode

Basile Kawkabani, Christophe Nicolet, Alexander Schwery

This paper presents the modeling, simulation and analysis of the dynamic behavior of a hydroelectric power plant of 2x343 MVA including hydraulic system, electrical installations, rotating inertias and control systems. First, the modeling of the electrical ...

Ieee2013

Simulation of water column separation in Francis pump-turbine draft tube

François Avellan, Christophe Nicolet, Sébastien Alligné

The paper presents the modelling, simulation and analysis of the transient behaviour of a 340 MW pump-turbine in case of emergency shutdown in turbine mode with focus on possible draft tube water column separation. The model of a pumped storage power plant ...

International Association For Hydraulic Research2012

Parametric study of water column separation in Francis pump-turbine draft tube

François Avellan, Christophe Nicolet, Sébastien Alligné

The paper presents the modelling, simulation and analysis of the transient behaviour of a 340 MW pump-turbine in case of emergency shutdown in generation mode with particular attention to the possible draft tube water column separation. First, the model of ...

Soc Hydrotechnique France2012

Numerical Modeling of Annular Laminar Film Condensation in Circular and Non-Circular Micro-Channels under Normal and Micro-Gravity

Stefano Nebuloni

A theoretical and numerical model to predict film condensation heat transfer in mini, micro and ultra micro-channels of different internal shapes is presented in this thesis. The model is based on a finite volume formulation of the Navier-Stokes and energy ...

EPFL2010

Unstable Operation of Francis Pump-Turbine at runaway: Rigid and Elastic Water Column Oscillation Modes

François Avellan, Jean-Jacques Simond, Basile Kawkabani, Sébastien Alligné

This paper presents a numerical simulation study of the transient behavior of a 2x340MW pump-turbine power plant, where the results show an unstable behavior at runaway. First, the modeling of hydraulic components based on equivalent schemes is presented. ...

2009

Transient Behavior of variable speed pump-turbine units

François Avellan, Jean-Jacques Simond, Basile Kawkabani, Christophe Nicolet, Yves Pannatier, Alexander Schwery

This paper presents the modeling, simulation and analysis of the dynamic behavior of a fictitious 2x320 MW variable speed pump-turbine power plant including hydraulic system, electrical installations, rotating inertias and control systems. First, the model ...

International Association For Hydraulic Research2008

Hydro Elastic Behavior of Vibrating Blades

François Avellan, Mohamed Farhat, Philippe Ausoni, Cécile Münch-Alligné, Olivier Braun

Fluid-structure investigations in hydraulic machines using coupled simulations are extremely time-consuming; therefore we develop an alternative method. In this paper, a model is proposed to predict fluid-structure coupling by linearizing the hydrodynamic ...

International Association For Hydraulic Research2008

Brownian motion studied with an optical trap

Branimir Lukic

This thesis describes measurements of Brownian motion of a colloidal particle using optical trapping. Two aspects are investigated: (i) influence of inertial effects on Brownian motion, and (ii) effect of the optical trap on Brownian motion. The first part ...

EPFL2008

Dynamic Behavior of a 2 Variable Speed Pump-Turbine Power Plant

Jean-Jacques Simond, Philippe Allenbach, Basile Kawkabani, Yves Pannatier

This paper presents the modeling, simulation and analysis of the dynamic behavior of a fictitious 2times320 MW variable speed pump-turbine power plant including hydraulic system, electrical equipments, rotating inertias and control systems using the softwa ...

2008

Hydroacoustic modelling and numerical simulation of unsteady operation of hydroelectric systems

Christophe Nicolet

Hydropower represented in 1999 19% of the world electricity production and the absolute production is expected to grow considerably during the next 30 years. Francis turbines play a major role in the hydroelectric production due to their extended range of ...

EPFL2007

Hydrodynamics of the free surface flow in Pelton turbine buckets

Alexandre Perrig

The design of Pelton turbines has always been more difficult than that of reaction turbines, and their performances lower. Indeed, the Pelton turbines combine 4 types of flows: (i) confined, steady-state flow in the piping systems and injector, (ii) free w ...

EPFL2007