COUPLING ELEMENT OF AN ULTRASONIC TRANSDUCER FOR AN ULTRASONIC, FLOW MEASURING DEVICE

摘要

A coupling element of an ultrasonic transducer suitable for mode conversion of an acoustic longitudinal wave between an in-coupling surface and an out-coupling surface of the coupling element. The coupling element has a first and second interface with a predetermined medium. A first angle between the in-coupling surface and the first interface and a second angle between the first interface and the out-coupling surface are so selected that a transverse waves fraction is reflected on the first interface to the out-coupling surface. The first angle between the in-coupling surface and the first interface and a third angle between the first interface and the second interface are so selected that a longitudinal wave fraction is reflected on the first interface for second interface. A fraction of the longitudinal waves reflected to the second interface is reflected on the second interface back into the coupling element.