Unidirectional focusing of horizontally polarized shear elastic waves electromagnetic acoustic transducers for plate inspection

Generation of horizontally polarized shear waves in ferromagnetic materials using magnetostrictively coupled meander‐coil electromagnetic transducers

Electromagnetic Acoustic Transducers for Robotic Nondestructive Inspection in Harsh Environments

Elevated temperature, gamma radiation, and geometric constraints inside dry storage casks for spent nuclear fuel represent a harsh environment for nondestructive inspection of the cask and require that the inspection be conducted with a robotic system. Electromagnetic acoustic transducers (EMATs) using non-contact ultrasonic transduction based on the Lorentz force to excite/receive ultrasonic w...

Dynamic Soil Sensing via Horizontally-polarized Shear Waves

This paper investigates the feasibility of site characterization via spectral analysis of horizontally-polarized shear (SH) waves as a means to lter the eeects of pore water for saturated soil conditions. Using a multi-layered wave propagation model to simulate the proposed testing connguration revolving around a torsionally vibrating loading plate, it is shown that the use of generalized Love ...

On Frequency-Focusing Unidirectional Waves

Phase convergence to within lOin mechanically generated waves was achieved at a specified point in a wave flume by frequency focusing. Owing to the presence of nonlinear waves, the crest elevation reaches a maximum somewhat further from the waveboard, where also breaking occurs if the waves are of sufficient size. The critical amplitude for breaking was not in close agreement with previous meas...

Optimization of a Focusable and Rotatable Shear-Wave Periodic Permanent Magnet Electromagnetic Acoustic Transducers for Plates Inspection

Due to the symmetry of conventional periodic-permanent-magnet electromagnetic acoustic transducers (PPM EMATs), two shear (SH) waves can be generated and propagated simultaneously in opposite directions, which makes the signal recognition and interpretation complicatedly. Thus, this work presents a new SH wave PPM EMAT design, rotating the parallel line sources to realize the wave beam focusing...