Band gaps and waveguiding of Lamb waves in stubbed phononic plates

摘要

Lamb wave propagation in a surface-stubbed phononic-crystal plate is investigated numerically and experimentally. Results show that the complete band gaps and flat bands of elastic waves exist in the structure. By using laser ultrasonic techniques, the experimental measurements demonstrate the evidence of the band gaps and resonances at the band-edge frequencies. In addition, a frequency range associated with the deaf bands is found. Based on the verified band gaps and deaf bands, waveguiding effects in the structure with a line defect are characterized. Furthermore, a sharply bent waveguide is then designed and fabricated to experimentally demonstrate frequency selection for broadband Lamb waves.