Articles techniques et présentations

Problem - The occlusion effect is an increase in loudness (sound pressure level) of your internal voice, especially in the low frequency range. Also, self-generated sounds such as chewing, swallowing, walking or running are amplified when the ears are blocked or occluded. Occlusion ... En savoir plus

When a material is subjected to a sudden change in electric field, the polarization of the material takes a finite time to respond – this phenomenon is referred to as dielectric relaxation. Dielectric relaxation is critical to understanding the important analytic technique of impedance ... En savoir plus

Microwave heating for CO_2 desorption provides fast, low-temperature desorption, lowering energy requirements in carbon capture. According to studies, microwaves generate selective heating, dramatically increasing desorption rates compared to traditional approaches. This new technique ... En savoir plus

The frequency dependent electrical impedance of porous media is studied by modelling the charge transport in the electrolyte filled pore space using COMSOL Multiphysics.  The corresponding experimental method, called Spectral Induced Polarization (or Impedance Spectroscopy), shows a ... En savoir plus

A magnetic field associated with current carrying coil(s) extends towards infinity, but an analytical model is of finite size. In the finite element analysis (FEA) of electromagnetic systems, open space needs to be modelled as close to reality as possible to get reliable results without ... En savoir plus

Ultrasonic flow-cell reactors are used for many industrial applications, where fluid substrate is sonicated in a small region, where very high ultrasonic acoustic power is present. The electromechanical transducer (converter) that drive the sonotrode inside the flow-cell is designed in ... En savoir plus

This paper presents a new design methodology of quasi-conformal transformation optics (QCTO) based modified Luneburg lens antennas using a broadband anti-reflective (AR) layer. The design used QCTO technique to modify portion of the lens’s spherical geometry into a flat surface for ... En savoir plus

Cylindrical grinding has become an integral part of machining of workpieces with an ultra-high precision and higher throughput. The grinding process involves the mechanical interaction of the grinding blade with the workpiece at relatively higher rotation speeds, with a higher energy ... En savoir plus

A substantial campaign of simulations was recently launched in the Bonomi Group with the goal of improving the understanding of the multiphysics involved in high voltage equipment such as aerial power lines, insulators, surge protectors and disconnectors. The activity not only resulted ... En savoir plus

Electret condenser microphones are one of the most used transducers for a variety of applications. The engineer designing these cartridges must take into consideration many factors to create a design that meets its specifications. Most parts of the design have multiple constraints across ... En savoir plus