Ultrasonic device for real-time sewage velocity and suspended particles concentration measurements.

In the frame of a technological research and innovation network in water and environment technologies (RITEAU, Réseau de Recherche et d'Innovation Technologique Eau et Environnement), our research group, in collaboration with industrial partners and other research institutions, has been in charge of the development of a suitable flowmeter: an ultrasonic device measuring simultaneously the water flow and the concentration of size classes of suspended particles. Working on the pulsed ultrasound principle, our multi-frequency device (1 to 14 MHz) allows flow velocity and water height measurement and estimation of suspended solids concentration. Velocity measurements rely on the coherent Doppler principle.

Modeling NDT piezoelectric ultrasonic transmitters.

Ultrasonic NDT applications are frequently based on the spike excitation of piezoelectric transducers by means of efficient pulsers which usually include a power switching device (e.g. SCR or MOS-FET) and some rectifier components.

Electrostatic Russian quadruplet with high demagnification and minimum influence of geometric aberrations.

Based on a combined analytical and numerical modelling, a high-quality probe-forming system is proposed and developed. The Matrizant method is applied to minimize the beam spot size for a fixed beam current. For quadrupoles consisting of four metallic rods, the electric field inside of the quadruplet is computed using an accurate version of the boundary element method.