A Research of the Sound Absorption Coefficient Measurement Method Based on the Sound Pressure Spectrum Analysis
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摘要: 吸声系数是表征吸声材料吸声性能的一个重要参数。在待测的吸声材料近前方布置一个麦克风,声波随机入射到吸声材料,利用麦克风检测麦克风所在位置的声压,将声压利用频谱式表示,利用傅里叶变换成为倒频谱,再与入射声源声压的倒频谱进行对比,即可得到吸声材料表面的反射系数,从而得出吸声材料的吸声系数。对不同种类的吸声材料实验验证,该方法测量得到的吸声系数与用驻波管方法在所测量的在相同频率内误差不大,证明了该方法对吸声系数测量的可行性。Abstract: Absorption coefficient is an important parameter of sound-absorbing function for the sound-absorbing ma-terial.A new method to measure sound absorption coefficient is presented in this paper,its main steps include:decorate a microphone nearly in front of the under-testing sound-absorbing material,and measure sound pressure at the location of the microphone while the sound wave randomly rip into the absorption material,and use the Fourier transformer to transform the sound pressure into inverted frequency spectrum;then compare the inverted frequency spectrum of the incident sound pressure to get the reflection coefficient on the surface of the sound absorption,final-ly obtain the sound absorption coefficient of the absorption material.Experiment results for different kinds of sound absorption material indicated that the measurement error of this new measuring method is acceptable within the same frequency compared by the standing wave tube method,which proved the feasibility of this method on absorption coefficient measurement.
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Key words:
- absorption coefficient /
- absorption /
- experiments
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