消声室的纯音自由声场计算及分析

Calculation and Analysis of Free Sound Field Deviation of Tones in Anechoic Room

介绍了消声室的纯音自由声场偏差计算原理,引入了3种不同的计算方法,讨论了3种不同方法的区别。并以南京大学消声室的尺寸为例,对不同频率的纯音信号的自由声场偏差进行计算。最后对计算结果进行讨论,指出如果各个频率的吸声系数都是0.99,高频信号的自由声场偏差大于低频信号,因此消声室的吸声要求应更关注高频部分,而截止频率这个指标在消声室的建设中并没有太多的实际指导意义。

It is introduced firstly that the caculation principle of the free sound field deviation of the tones in the anechoic room, there are three caculation methods, and the differences among them are discussed. And then based on the size of the anechoic room in the Nanjing University, the free sound field deviation of the tones with different frequency have been calculated.The conclusions have been drawn from the results that the free sound field deviation in the high frequency range are larger than those in the low frequency range if the sound absorbtion indices of all frequency are 0.99, so the sound absorbtion of the high frequency in the anechoic room should been more attention, and the instruct significance of the cut-off frequency in the anechoic room is absent.