三维声强阵列测试精度的对比及数值分析

Comparison and Numerical Analysis of Measurement Accuracy of Two Three-Dimensional Sound Intensity Arrays

针对四面体及六传声器布置形式的声强阵列测试精度进行数值计算,比较了两种阵列的幅值测量误差及方向判断误差,并通过消声室的测试分析验证数值计算结果.研究结果表明:随着频率的升高,声强测量的幅值误差也相应增加;声强阵列的半径小于0.012 7 m时,频率为6 k Hz时两者测量幅值误差均超过2 d B.在方向性误差判断方面,四传声器比六传声器存在较大的优势.在kd(波数与传声器声强阵列半径的积)小于1.6时,四传声器声强阵列的方向误差判别小于1°.四传声器声强阵列降低了声强测量的硬件系统要求,但在中频阶段完全可以用于相关的建筑声学测试.

In this paper,the measurement accuracies of the sound intensity arrays of the tetrahedral and six-microphone arrangements are numerically predicted,and the measured amplitude and angle biases of the two arrays are compared. Then,the numerical results are verified by a test in an anechoic room. The results show that（ 1） the measured amplitude errors of the two arrays increase with the frequency,and they are both greater than 2 d B when the frequency is 6 k Hz and the sound intensity array radius is less than 0. 012 7 m;（ 2） the tetrahedron is significantly superior to the six microphone in terms of the angle bias,and the angle bias of the tetrahedron is less than 1°when kd（ the product of the wave number and the sound intensity array radius） is less than 1. 6; and（ 3） the tetrahedral sound intensity array reduces the requirement for the hardware system of the sound intensity measurement and can be used in relevant architecture acoustical measurements at the intermediate frequency stage.