MIN Qi1,2 DUAN Hong1 PENG Feng1 YIN Yap1 LIU Ke1

(1 Key Laboratory of Noise and Vibration Research, Institute of Acoustics, Chinese Academy of Sciences  Beijing  100190)

(2 Honghe University  Yunnan  661100)

Received Feb.18, 2010

Revised Mar.10, 2010

Abstract Standing-wave tube with abrupt section (STAS) was a dissonant standing-wave tube whose higher resonance frequencies were not integral multiplies of the first one. Making use of the dissonant property of STAS and through the optimization of the system, extremely nonlinear pure standing-wave field of 180 dB at the first resonance frequency and that of 177 dB at the second resonance frequency have been obtained. At the two resonance frequencies,distortion of waveform and saturation of harmonics were studied experimentally, but saturation did not appear even though under such high sound pressure levels. However, while nonlinear sound field was experimentally studied at the third resonance frequency, it was found that the frequency for the second harmonic of the third resonance frequency was close to the sixth resonance frequency of the STAS and the distortion of waveform and the saturation of harmonics appeared as the sound pressure level approached 170 dB.

PACS numbers: 43.25