학술논문

Mapping of an acoustic field by analysis of bubbles trajectory
Document Type
Conference
Source
1994 Proceedings of IEEE Ultrasonics Symposium Ultrasonics Ultrasonics Symposium, 1994. Proceedings., 1994 IEEE. 3:1363-1366 vol.3 1994
Subject
Signal Processing and Analysis
Fields, Waves and Electromagnetics
Components, Circuits, Devices and Systems
Engineered Materials, Dielectrics and Plasmas
Underwater acoustic propagation
Acoustic measurements
Language
Abstract
It has been noted that in a high intensity field a bubble is pushed away in the ultrasonic propagation direction. The main action of an intense sound field on bubbles are usually identified as radiation pressure and, due to this force, the bubble-velocity in acoustic propagation direction is proportional to the square of the pressure amplitude. Then, when a bubble rises up through an acoustic field, its movement provides pinpoint information about this field. Calibrated bubbles with a constant and reproducible size are produced one at a time from a capillary tip. As a first step the experiment is shot with a video. As a second step, images are digitized and processed. Using bubbles of a hundred microns as a sensor does not disturb the investigated field. In this paper, the experimental setup and the mapping of a 2 MHz transducer field at pressure amplitudes of about 10 4 Pa are presented