Review of coupled vibration problems in EMS maglev vehicles

Abstract

This paper presents numerical and experimental results concerning Lamb-wave actuation and reception in metallic or layered composite panels and pipes. The numerical simulations were carried out with LS-Dyna, run under ANSYS platform. The main goals of this approach were to find better models for actuating Lamb waves and tracking the wave transmission in order to get efficient in situ structural health monitoring. Prior adequate choice of the signal frequency using the dispersion curves proved to be beneficial for better transmission, in terms of signal detection, and it extended inspection range. The effects of the transducer-inspected item interface and transducer shape on the wave transmission were also evaluated. Signal generation with rectangular transducers, batteries of round piezoceramic transducer (PZT) patches or the use of prisms, which value Snell?s law, were alternatively considered for getting guided waves in the inspected item. The experiments showed the performance of various transducers and devices used on the experimental chain. The Lamb waves were generated by PZT, in various shapes and configurations, aiming to lower the inspection cost. Experiments always aligned with theoretical results so that robust models could be selected for further investigations.