Measurement of pressure on a surface using bubble acoustic resonances

作者：Aldham Ben^*; Manasseh Richard; Illesinghe Suhith; Liffman Kurt; Ooi Andrew; Sutalo Ilija D

来源：Measurement Science and Technology, 2010, 21(2): 027002.

DOI：10.1088/0957-0233/21/2/027002

• bubble acoustics
• pressure measurement
• coupled oscillator

The frequency response of gas bubbles as a function of liquid ambient pressure was measured and compared with theory. A bubble size with equivalent spherical radius of 2.29mm was used over a frequency range of 1000-1500 Hz. The ultimate aim is to develop an acoustic sensor that can measure static pressure and is sensitive to variations as small as a few kPa. The classical bubble resonance frequency is known to vary with ambient pressure. Experiments were conducted with a driven bubble in a pressurizable tank with a signal processing system designed to extract the resonant peak. Since the background response of the containing tank is significant, particularly near tank-modal resonances, it must be carefully removed from the bubble response signal. A dual-hydrophone method was developed to allow rapid and reliable real-time measurements. The expected pressure dependence was found. In order to obtain a reasonable match with theory, the classical theory was modified by the introduction of a 'mirror bubble' to account for the influence of a nearby surface.

• 出版日期2010-2
• 单位CSIRO