Title :
An experimental study of nonlinear frequency spectra of ultrasound transmission through two-dimensional microbubbles
Author :
Wu, J. ; Nyborg, W.L.
Author_Institution :
Dept. of Phys., Vermont Univ., Burlington, VT, USA
Abstract :
The frequency spectra of transmission coefficients for ultrasound passing through a sheet of gas-filled micropores have been measured using incident waves with amplitudes up to 2.4×104 Pa. It is found that as the amplitude of the incident wave is increased the peak frequency of transmission loss through the two-dimensional trapped-bubble ensemble shifts to lower values by as much as 47%. The experiments indicate that the shifting is caused by the net displacements of air-water-membrane triple lines and the air loss of the trapped bubble, which are due to the radiation force and microbubble production produced by the incident wave
Keywords :
bubbles; nonlinear acoustics; ultrasonic transmission; 24 MPa; air-water-membrane triple lines; frequency spectra; gas-filled micropores; incident wave; microbubble production; nonlinear frequency spectra; radiation force; transmission coefficients; transmission loss; two-dimensional microbubbles; two-dimensional trapped-bubble ensemble; ultrasound; ultrasound transmission; Biomembranes; Frequency measurement; Loss measurement; Physics; Predictive models; Propagation losses; Resonance; Resonant frequency; Ultrasonic imaging; Ultrasonic variables measurement;
Conference_Titel :
Ultrasonics Symposium, 1989. Proceedings., IEEE 1989
Conference_Location :
Montreal, Que.
DOI :
10.1109/ULTSYM.1989.67181
