Experimental study on the standing-wave tube with tapered section and its extremely nonlinear standing-wave field  

作　　者：MIN Qi YIN Yao LI Xiaodong LIU Ke 

机构地区：[1]Honghe University Yunnan 661100 [2]Key Laboratory of Noise and Vibration Research, Institute of Acoustics, Chinese Academy of Sciences Beijing 100190

出　　处：《Chinese Journal of Acoustics》2011年第4期409-416,共8页声学学报（英文版）

基　　金：supported by the National Natural Science Foundation of China(10574135);the Main Direction Program of Knowledge Innovation of Chinese Academy of Sciences(No.KJCX2-YW-W02)

摘　　要：A standing-wave tube with tapered section （STTS） was evolved from a standingwave tube with abrupt section （STAS） whose abrupt section was replaced with tapered section. The research was intended to compare the acoustic properties and the extremely nonlinear pure standing waves of STTS with those of STAS. The acoustic properties of the STTS were studied with transfer matrix. It was proved, like the STAS, that the STTS was dissonant standingwave tube. With its dissonant property, the 181 dB extremely nonlinear pure standing wave was obtained in the STTS excited at its first resonance frequency. Then the comparative experimental studies on the saturation properties of the extremely nonlinear standing waves were carried out in the STTS and the STAS with the same length. It was found that the STTS could suppress the harmonics and meanwhile reduce energy loss of the standing wave more effectively. Compared with the STAS, under the same voltage of loudspeaker, the STTS obtained a higher extremely nonlinear pure standing wave. Moreover, it was found for the STTS that the third harmonic of the third resonance frequency was close to the seventh resonance frequency of sound source impedance, to which the valley value of the sound pressure level transfer function corresponded. Because of this, the third harmonic increased rapidly with the increase of fundamental wave and tended to saturate.

关 键 词：驻波管 非线性 实验 共振频率 三次谐波 声学特性 饱和特性 转移矩阵 

分 类 号：TP368.1[自动化与计算机技术—计算机系统结构] O422.7[自动化与计算机技术—计算机科学与技术]