Long Distance Leaky Surface Ultrasonic Waves

摘要

This paper contains a description of an unique wave that was created in a two plate system separated by a layer of water. First, a Lamb wave was created in the upper plate by placing a transducer on a wedge on top of the plate at an appropriate angle and frequency. This wave was created to act like quasi-Rayleigh (surface) waves on both surfaces of the plate. The wave on the bottom surface of the upper plate then leaked through the water into the upper surface of the lower plate. We will show both experimentally and theoretically that the wave on the surfaces of the plates in contact with the water leak constructively to create a leaky-wave that can travel great distances. The cooperative behaviour was modelled on a computer.