Publications related to Bernoulli's principle

MIXING FOR GENERIC ROUGH SHEAR FLOWS

We study mixing and diffusion properties of passive scalars driven by generic rough shear flows. Genericity is here understood in the sense of prevalence, and (ir)regularity is measured in the Besov-Nikolskii scale B\alpha 1,\infty, \alpha \in (0,1). We pr ...

Siam Publications2023

Dielectric Elastomer Actuator-Based Valveless Impedance-Driven Pumping for Meso- and Macroscale Applications

Yves Perriard, Yoan René Cyrille Civet, Thomas Guillaume Martinez, Francesco Clavica, Armando Matthieu Walter, Amine Benouhiba, Silje Ekroll Jahren

Impedance pumps are simple designs that allow the generation or amplification of flow. They are fluid-filled systems based on flexible tubing connected to tubing with different impedances. A periodic off-center compression of the flexible tubing causes the ...

2023

Mixing and diffusion for rough shear flows

Maria Colombo, Klaus Martin Widmayer

This article addresses mixing and diffusion properties of passive scalars advected by rough (

C^\alpha

) shear flows. We show that in general, one cannot expect a rough shear flow to increase the rate of inviscid mixing to more than that of a smooth shear ...

2021

Pressure on obstacles induced by granular snow avalanches

Michael Lukas Kyburz

The increasing population and the consequential demand for dwelling and recreation areas lead to more frequent conflicts between humans and natural hazards. In mountainous regions snow avalanches are, therefore, still a major threat to humans and infrastru ...

EPFL2021

Hydrodynamic mechanisms of aggressive collapse events in leading edge cavitation

Mohamed Farhat, Ali Amini

Transient cavities generated from unsteady leading-edge cavitation may undergo aggressive collapses which are responsible for cavitation erosion. In this paper, we studied the hydrodynamic mechanisms of these events in the leading edge cavitation formed ov ...

SPRINGER2020

Unsteady Radiative Heat Transfer Model of a Ceria Particle Suspension Undergoing Solar Thermochemical Reduction

Sophia Haussener, Aldo Steinfeld, Tristan Elias Breuillé

Unsteady radiative heat transfer is analyzed numerically in a directly irradiated plane-parallel medium containing a suspension of ceria particles undergoing nonstoichiometric thermal reduction. The micrometer-sized ceria particles are assumed homogenous, ...

AMER INST AERONAUTICS ASTRONAUTICS2019

Steady Three-Dimensional Rotational Flows: An Approach Via Two Stream Functions And Nash-Moser Iteration

Boris Buffoni

We consider the stationary flow of an inviscid and incompressible fluid of constant density in the region D = (0, L) x R-2. We are concerned with flows that are periodic in the second and third variables and that have prescribed flux through each point of ...

MATHEMATICAL SCIENCE PUBL2019

Experimental Characterization of a T-Shaped Programmable Multistable Mechanism

Simon Nessim Henein, Mohamed Gamal Abdelrahman Ahmed Zanaty

Programmable multistable mechanisms (PMM) exhibit a modifiable stability behavior in which the number of stable states, stiffness, and reaction force characteristics are controlled via their programming inputs. In this paper, we present experimental charac ...

2018

Non-uniqueness of admissible weak solutions to the Riemann problem for isentropic Euler equations

Elisabetta Chiodaroli

We study the Riemann problem for multidimensional compressible isentropic Euler equations. Using the framework developed in Chiodaroli et al (2015 Commun. Pure Appl. Math. 68 1157-90), and based on the techniques of De Lellis and Szekelyhidi (2010 Arch. Ra ...

IOP PUBLISHING LTD2018

$A$-free Rigidity and Applications to the Compressible Euler System

Elisabetta Chiodaroli

Can every measure-valued solution to the compressible Euler equations be approximated by a sequence of weak solutions? We prove that the answer is negative: Generalizing a well-known rigidity result of Ball and James to a more general situation, we constru ...

2017

Unsteady fluid dynamics around a hovering flat plate wing

Swathi Badala Krishna

Insect flight is characterised by complex time-dependent flows in response to the unsteady wing movements. Biological fliers exploit the unsteady flow fields to modulate aerodynamic forces, thereby displaying unmatched flight performance, especially in hov ...

EPFL2017

Collapse phenomena of deformed cavitation bubbles

Outi Supponen

Cavitation bubbles are a topic of long-standing interest owing to the powerful phenomena associated with their collapse. Their unique ability to focus energy typically causes damage in hydraulic machinery (turbines, pumps, propellers, ...) but, if managed ...

EPFL2017

Fluid-structure interaction mechanisms leading to dangerous power swings in Francis turbines at full load

François Avellan, Arthur Tristan Favrel, Christian Landry

Hydropower plants play an important regulatory role in the large scale integration of volatile renewable energy sources into the existing power grid. This duty however requires a continuous extension of their operating range, provoking the emergence of com ...

Elsevier2017

An overview of some recent results on the Euler system of isentropic gas dynamics

Elisabetta Chiodaroli

This overview is concerned with the well-posedness problem for the isentropic compressible Euler equations of gas dynamics. The results we present are in line with the programof investigatingthe efficiency of different selection criteria proposed in the li ...

Springer Heidelberg2016

Stresses and displacements in steel-lined pressure tunnels and shafts in anisotropic rock under quasi-static internal water pressure

Anton Schleiss, Alexandre Jean Pachoud

Steel-lined pressure tunnels and shafts are constructed to convey water from reservoirs to hydroelectric power plants. They are multilayer structures made of a steel liner, a cracked backfill concrete layer, a cracked or loosened near-field rock zone and a ...

Springer Wien2016

Experimental and Numerical Assessment of the Aeroelastic Stability of Blade Pair Packages

Peter Ott, Achim Zanker

The stabilizing effect of grouping rotor blades in pairs has been assessed both, numerically and experimentally. The bending and torsion modes of a low aspect ratio high speed turbine cascade tested in the non-rotating test facility at EPFL (Ecole Polytech ...

ASME2014

Discussion of "Skimming, Nonaerated Flow on Stepped Spillways over Roller Compacted Concrete Dams" by Ines Meireles, Floriana Renna, Jorge Matos, and Fabian Bombardelli

Michael Pfister

The nonaerated region may occupy a large portion of the skimming flow in steep, stepped spillways, particularly for relatively high unit flow rates. In spite of the numerous contributions on the hydraulic properties at both the inception point of air entra ...

American Society of Civil Engineers2014

A counterexample to well-posedness of entropy solutions to the compressible Euler system

Elisabetta Chiodaroli

We consider entropy solutions to the Cauchy problem for the isentropic compressible Euler equations in the spatially periodic case. In more than one space dimension, the methods developed by De Lellis-Szekelyhidi enable us to show here failure of uniquenes ...

World Scientific Publ Co Pte Ltd2014

Proof of principle demonstration of a self-tracking concentrator

Christophe Moser, Eric Tremblay, Volker Günter Zagolla

We present to the best of our knowledge the first successful demonstration of a planar, self-tracking solar concentrator system capable of a 2-dimensional angular acceptance of over 40 degrees. The light responsive mechanism allows for efficient waveguide ...

Optical Society of America2014

Image analysis technique applied to lock-exchange gravity currents

Mário Jorge Rodrigues Pereira Da Franca, Helena Isabel Dos Santos Nogueira, Claudia Adduce

An image analysis technique is used to estimate the two-dimensional instantaneous density field of unsteady gravity currents produced by full-depth lock-release of saline water. An experiment reproducing a gravity current was performed in a 3.0 m long, 0.2 ...

Institute of Physics2013