Articles techniques et présentations

Phonons underlie the propagation of sound and the transport of heat in materials. With outstanding progress in the design of phononic crystals, it is now feasible to control the acoustic properties of these materials and to endow them with unique acoustic properties. For instance, it ... En savoir plus

Macroscale ultrasonic separation is a new filtration technology, with various applications such as cell clarification, cell therapy, blood-lipid separation, oil-water separation etc. These systems use piezoelectric transducers to create standing waves in fluid-particle mixture. Suspended ... En savoir plus

Teledyne Marine developed a system for the long-range ocean acoustic tomography, which uses a tunable, high-efficiency sound resonator. The high-Q resonator tunes to match the frequency and phase of a reference frequency-modulated signal. The analysis of a high-Q resonant organ pipe with ... En savoir plus

A frequency-domain finite element (FE) technique for computing the acoustic scattering from axially symmetric fluid-loaded structures subject to a nonsymmetric forcing field based on Ref. 1 is extended to poroelastic media and implemented in COMSOL Multiphysics® software. This method ... En savoir plus

Tonal noise from wind turbines can have effects on neighboring residences and its emission can result in strong regulatory penalties that can include the closure of wind farms. The authors present a model of a new broadband damping approach where containers filled with EniDamp™, an ... En savoir plus

The assessment of the seismic safety of gravity dams is a topic of great importance in civil engineering. In this paper, fluid structure interaction modeling of gravity dams during earthquakes is investigated. In particular, this work aims to provide physical significance of a plan ... En savoir plus

An electrostatic headphone includes many interrelated design elements that affect the frequency response of the headphone and the users listening experience. Xi Engineering Consultants (XI) partnered with Warwick Audio Technologies (WAT) to investigate the complex behavior of one-side ... En savoir plus

The vibration behavior of carbon fiber reinforced composites (CFRP) specimens with impact damage is presented in order to evaluate if an before/after modal analysis can be used as a non-destructive testing method to detect delaminations. The impact damage is modeled by decreasing the ... En savoir plus

For automotive applications, simulation methods are used to get the best audio acoustic performance. Because a loudspeaker is a non linear device, the sound pressure in the vehicle includes harmonics which are mainly created by the force factor, suspension stiffness and voice coil ... En savoir plus

When the particles in a colloid come close to each other, multiple scattering in ultrasonic beams is no longer negligible and crowded particle effects emerge. The presence of each particle affects the scattering of all others, leading to coupling effects. We investigate the interaction ... En savoir plus