Abstract
The majority of reported measurements on high intensity ultrasound beams in air are below 40 kHz and are performed on standing waves inside a guide. Here we present experimental characterization of high intensity progressive and divergent sound beams in air at 300 kHz. Measurements in this frequency range are challenging. Accurate characterization of high intensity sound beams requires a measurement bandwidth at least 10x the beam's primary frequency, as high intensity soundwaves steepen and form shocks, and therefore contain significant signal power at harmonic frequencies. A measurement bandwidth of at least 3 MHz is therefore required. Calibrated measurement microphones are generally not available in this frequency range. We have overcome this limitation by using a hydrophone with a calibrated response from 250 kHz—20 MHz. A narrowband piezoelectric transducer is used as the source in this study. The source is capable of generating tone burst waveforms centered at 300 kHz and with 160 dB SPL surface pressure. Cumulative wave steepening and shock formation are observed in on-axis measurements. The source's surface vibration profile is measured using a scanning LDV, and the vibration profile is imported into a numerical wide-angle KZK simulation for comparison against measured on-axis waveforms.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
