• The Analysis of Acoustic Emission Spectra in a 36 kHz Sonoreactor
  • Son, Younggyu;
  • Department of Environmental Engineering, Kumoh National Institute of Technology;
  • 36kHz 초음파 반응기에서의 원주파수 및 파생주파수의 음압 분포 분석
  • 손영규;
  • 국립금오공과대학교 환경공학과;
Abstract
Acoustic emission spectra was analyzed to investigate the distribution of sound pressure in a 36 kHz sonoreactor. The sound pressure of fundamental frequency (f: 36 kHz), harmonics (2f: 72 kHz, 3f: 108 kHz, 4f: 144 kHz, 5f: 180 kHz, 6f: 216 kHz), and subharmonics (1.5f: 54 kHz, 2.5f: 90 kHz, 3.5f: 126 kHz, 4.5f: 162 kHz, 5.5f: 198 kHz, 6.5f; 234 kHz) was measured at every 5 cm from the ultrasonic transducer using a hydrophone and a spectrum analyzer. It was revealed that the input power of ultrasound, the application of mechanical mixing, and the concentration of SDS affected the sound pressure distributions of the fundamental frequency and total detected frequencies frequencies significantly. Moreover a linear relationship was found between the average total sound pressure and the degree of sonochemical oxidation while there was no significant linear relationship between the average sound pressure of fundamental frequency and the degree of sonochemical oxidation.

Keywords: Acoustic emission spectra;Sound pressure;Fundamental frequency;Harmonics;Subharmonics;Sonochemical reactions;

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