Articles techniques et présentations

IntroductionThe application of power ultrasounds in food dehydration processes have shown a good performance in terms of efficiency, energy reduction and quality of the final product, allowing also a reduction in the convective drying kinetics, and at lower temperatures than conventional ... En savoir plus

In our work, simulations of a piezoelectrical micromachined ultrasonic transducer compatible with CMOS-MEMS process are presented. The piezoelectric material of the PMUT is AlN sandwiched between two Al layers and a top Si3N4 passive layer. The piezoelectric and the metal materials have ... En savoir plus

Finite Element simulations are becoming an increasingly powerful tool in the transducer design process. The development of user-friendly software and predefined interfaces able to provide physics setup to predict the loudspeaker complex behavior helps designers in the product development ... En savoir plus

For active Structural Health Monitoring (SHM), one popular sensor type is the piezoelectric wafer active sensor (PWAS) due to its multi-purpose application as actuator and sensor and its low cost. It is used to generate a wave field, which interacts with the structure and is recorded by ... En savoir plus

Photoacoustic (PA) imaging has matured into a clinical modality for tissue imaging and functional cancer cell research. It uses a pulsed laser to irradiate a region and generate a thermally-induced acoustic pressure wave that can be collected by an ultrasound transducer. The optical ... En savoir plus

The self heating process of Tetrafluoroethylene caused by an exothermic dimerization reaction was studied. The heat of reaction can lead to a thermal explosion by the decomposition of the Tetrafluoroethylene. Different reaction kinetics, including multistep kinetics, were used to ... En savoir plus

The acoustoelastic effect relates the change in the speed of an acoustic wave travelling in a solid, to the pre-stress of the propagation medium. In this work the possibility of assessing nondestructively the stress status in metal sheets, by using the acoustoelastic effect, is ... En savoir plus

A scheme for inductive wireless powering and readout of passive LC sensor is presented. The sensor’s inductor is designed as a planar square coil and is used as the power receiving component. The capacitor is connected directly to the inductor and it was designed as an interdigital ... En savoir plus

The simulation of a large acoustic cylindrical antenna made of numerous identical transducers is very often out of reach in terms of computational cost. Therefore the usual design procedure consist in optimizing the transducer standing alone, either in free field arrangement or sitting ... En savoir plus

Ultrasound is a promising green technology for the advanced oxidation process (AOP) since it adds no chemicals to the treated water. In this paper, COMSOL Multiphysics® was used as a tool to design and characterize an ultrasound irradiator with multi-stepped configuration, which aims to ... En savoir plus