Frequency Dependent Sound Radiation of Ultrasonic Wedge Transducers

Abstract:
The direction under which an ultrasonic wedge transducer radiates sound into an adjacent medium is usually calculated by Snell’s law. By analysis of the refracted wave field, it can be shown that the orientation of the emitted sound waves are dependent on the transducer’s excitation frequency, in addition to the angle of incidence and the involved speeds of sound. The investigation is conducted using a modified Hough transform, which allows to precisely determine the orientation of single wavefronts. The algorithm is applied to simulation and measurement data. A Schlieren imaging system is used for the acquisition of measurement data.