基于声场重建的材料吸声系数测量方法  

Method for measuring material sound absorption coefficient based on sound field reproduction

作　　者：张燕凯[1] 匡正[1] 吴鸣[1] 杨军[1] 

机构地区：[1]中国科学院噪声与振动重点实验室(声学研究所),北京100190

出　　处：《应用声学》2017年第1期1-8,共8页Journal of Applied Acoustics

基　　金：国家自然科学基金项目(11304349;11504405)

摘　　要：针对现有方法对材料吸声系数进行现场测量时存在低频测量误差大的问题,本文提出了一种利用扬声器线阵列对材料吸声系数进行现场测量的新方法。该方法使用基于能量比值约束的最小二乘法在待测材料表面进行平面波声场重建并结合双传声器传递函数法对材料的吸声系数进行测量。数值仿真表明在100～1600 Hz频率范围内,新方法在未加约束时能够对材料的吸声系数进行准确测量。在半消声室中利用新方法测量了三聚氰胺泡沫的吸声系数,分析了能量比值约束值对测量结果的影响,并和阻抗管以及其它两种现场测量方法的测量结果进行了对比。结果表明该方法能够对吸声材料在160～1600 Hz频段内的吸声系数进行准确测量,并且相较于现存的现场测量方法,新方法具有更低的测量频率下限。The existing methods which measure the absorption coefficient of sound absorbing material insitu cannot achieve precise measurement at low frequencies.To solve this problem,a new method for in-situ measurement of material absorption coefficient using a linear loudspeaker array is proposed in this paper.Plane-wave sound field is reproduced in front of the material surface by using the least square method with energy contrast control and the transfer function method is applied to measure material absorption coefficient.Numerical simulations show that,in the frequency range of 100~1600 Hz,this method without energy contrast control can accurately measure the absorption coefficient of sound absorbing material.In a semi-anechoic chamber,we apply the proposed method to measure the absorption coefficient of melamine and analyze how the energy contrast value affects the measurement results.Compared with the values measured with the impedance tube method,the proposed method and two other existing in-situ measurement methods,the results show that the proposed method can give accurate measurement over 160~1600 Hz and the lower measurement limit than the existing in-situ measurement methods.

关 键 词：声场重建 能量比值约束 最小二乘法 吸声系数 现场测量 

分 类 号：O422.2[理学—声学]