Experimental assessment of an active (acoustic) liner prototype in an acoustic flow duct facility

Chattez avec Graph Search

Posez n’importe quelle question sur les cours, conférences, exercices, recherches, actualités, etc. de l’EPFL ou essayez les exemples de questions ci-dessous.

AVERTISSEMENT : Le chatbot Graph n'est pas programmé pour fournir des réponses explicites ou catégoriques à vos questions. Il transforme plutôt vos questions en demandes API qui sont distribuées aux différents services informatiques officiellement administrés par l'EPFL. Son but est uniquement de collecter et de recommander des références pertinentes à des contenus que vous pouvez explorer pour vous aider à répondre à vos questions.

This study investigates experimentally hydraulic fracture propagation, arrest and closure in permeable rocks.Through a controlled laboratory experiment on a Molasse sandstone block under a true triaxial state of stress, hydraulic fracture propagation and c ...

The design and the grazing flow aeroacoustical characterization of a 2D active liner based on an array of electroacoustic absorbers are presented in this paper. The strategy stands on a pressure-based, current-driven digital architecture for impedance cont ...

This paper is focused on experimental characterization of new active liners technologies in acoustic flow duct facilities (FDF). These measurements have been performed in the NLR (Netherlands Aerospace Center). Different configurations of passive and activ ...

This study presents an experimental work on dynamic pressures at the bottom of a lined plunge pool that receives overflow rectangular impinging jets and aims at improving the design criteria for pool slabs. The experiments were conducted in a fairly large ...

Experimental studies suggest that the fracture toughness of rocks increases with the confining pressure. Among many methods to quantify this dependency, a so-called burst experiment (Abou-Sayed, 1978) may be the most widely applied in practice. Its thick w ...

Fluctuating bottom-pressures on stepped chutes are relevant for the spillway design. An abrupt slope reduction causes a local alteration of the bottom-pressure development. Little information is available regarding the air–water flow properties near an abr ...

Two ways for producing a transport barrier through strong shear of the E x B poloidal flow have been investigated using GYSELA gyrokinetic simulations in a flux-driven regime. The first one uses an external poloidal momentum (i.e. vorticity) source that lo ...

The calculation of the impact pressure on obstacles in granular flows is a fundamental issue of practical relevance, e.g. for snow avalanches impacting obstacles. Previous research shows that the load on the obstacle builds up, due to the formation of forc ...

Occurrence of cavitation in hydraulic machines is a challenging issue because it is often accompanied with loss of efficiency, noise emissions, vibrations, and erosion damages. Tip vortices, in particular, are an ideal site for the development of cavitatio ...

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 ...

We report a small-angle neutron scattering study of the helical and skyrmion lattice order in single-crystal Cu2OSeO3 under quasihydrostatic helium gas pressures up to 5 kbar. By using helium gas as the pressure-transmitting medium (PTM) we ensure pressure ...

At part load conditions, Francis turbines are subject to the emergence of a hydrodynamic instability in their draft tube, referred to as precessing vortex rope. It induces pressure pulsations in the water passages at the precession frequency of the vortex, ...

Understanding the physical processes involved in snow avalanche‐obstacle interaction is essential to be able to estimate the pressure exerted on structures. Although avalanche impact pressure has been measured in field experiments for decades, the underlyi ...

Nanopores are nanometer sized openings that are the connection between two electrolyte filled reservoirs. The measurement of the ion transport flowing through such a pore allows to probe physically or biologically interesting phenomena. These range from th ...

In order to increase their efficiency and power-density, turbomachines are continuously pushed to run faster, and hotter rotors. These requirements create enormous engineering challenges that affect the design of turbomachines down to the component level. ...

Numerical investigation of the unsteady flow patterns around the bucket can be helpful to improve the Pelton turbine efficiency. In fact, by studying the loss mechanisms in the flow, one can optimize the bucket design. For this purpose, an accurate investi ...

Flexible pressure sensors offer a wide application range in health monitoring and human–machine interaction. However, their implementation in functional textiles and wearable electronics is limited because existing devices are usually small, 0D elements, a ...

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 ...

Inception and desinence thresholds of tip vortex cavitation (TVC), generated by an elliptical NACA 16-020 hydrofoil, are measured at different flow conditions for various gas contents. It is observed that TVC often disappears at cavitation indices signific ...

The present research aims at understanding the mass transfer of air into water in a reversible pump turbine operating in condenser mode. In particular, the diffusion of oxygen through the water free-surface both in the vaneless gap between the impeller bla ...

Experimental assessment of an active (acoustic) liner prototype in an acoustic flow duct facility

Chattez avec Graph Search

Measuring hydraulic fracture propagation and closure in sandstone

In flow acoustic characterisation of a 2D active liner with local and non local strategies

2D ACTIVE LINER EXPERIMENTAL RESULTS IN ACOUSTIC FLOW DUCT FACILITY

Overflow pressure characterization in lined plunge pools for slab sizing

Improving the Accuracy of Fracture Toughness Measurement in Burst Experiments

Bottom-Pressure Development Due to an Abrupt Slope Reduction at Stepped Spillways

Transport barrier in 5D gyrokinetic flux-driven simulations

The concept of the mobilized domain: how it can explain and predict the forces exerted by a cohesive granular avalanche on an obstacle

Physical Mechanism and Flow Control of Tip Vortex Cavitation

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

In situ control of the helical and skyrmion phases in Cu2OSeO3 using high-pressure helium gas up to 5 kbar

Swirl number based transposition of flow-induced mechanical stresses from reduced scale to full-size Francis turbine runners

Decoupling the role of inertia, friction and cohesion in dense granular avalanche pressure build‐up on obstacles

Fundamental Applications of Nanopores: Controlled DNA Translocations to Nanofluidics

An Experimental Study of Gas Lubricated Foil Journal Bearings Using an Instrumented Rotor with Wireless Telemetry

Numerical investigation of the jet velocity profile and its influence on the Pelton turbine performance

Compressible and Electrically Conducting Fibers for Large‐Area Sensing of Pressures

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

On the physical mechanism of tip vortex cavitation hysteresis

Oxygen diffusion through air–water free surfaces in a pump–turbine operating in condenser mode