【作者】 刘栋； 吕亚东；

【Author】 LIU Dong,LU Ya-dong (The Key Laboratory of Noise and Vibration Research, Institute of Acoustics,Chinese Academy of Sciences,Beijing 100190,China)

【机构】 中国科学院声学研究所噪声与振动重点实验室；

【摘要】 温度变化能够影响空气的声速、密度和粘滞系数,进而影响吸声结构的吸声特性。以微穿孔板吸声体为例,进行了温度变化条件下微穿孔板吸声体吸声性能的仿真计算和对比。计算结果表明:温度升高时,共振频率提高,吸声频带半宽度变窄,半吸声点间的频程变小。在驻波管中开展了微穿孔板吸声体常温和底部冻冰情况下吸声性能对比实验,得出了以下结论:冻冰情况下微穿孔板吸声体的吸声系数也比常温情况有不同程度的提高,整体提高了吸声性能曲线,避免了微穿孔板吸声体某些频带的吸声性能谷底。这就为在不同温度环境下使用的微穿孔板吸声体设计提供了一定的参考依据。更多还原

【Abstract】 The changes in temperature can affect air sound speed,density and viscosity coefficient,so they may further influence sound absorption properties of sound absorbing structure. Taking a micro-perforated absorber as an example,under the circumstances of temperature changes, the numerical simulations of the sound absorption of the micro-perforated absorber are conducted in this paper.The computation results show that as the temperature increases,the resonance frequency becomes higher,and the absorption band half-width becomes less narrow,the frequency interval of the absorption band between the half-absorption points becomes smaller.In the cases of normal temperature and bottom icing of the micro-perforated absorber,the experimental comparisons of sound absorption of the micro-perforated absorber are carried out in an impedance tube.The following conclusions can be obtained that the micro-perforated absorber’s sound absorption coefficients in the case of bottom icing is higher than that in the case of normal temperature to some different extent,the whole sound absorption performance curve is increased,the sound absorption valley at some frequencies may be avoided.These studies provide some references for the design of the micro-perforated absorber under different temperature circumstances.更多还原