基于扫描声强法的声功率测量扫描路径误差研究

依据ISO9614-2标准，以单极子，偶极子和四极子声源为例，建立了矩形测量面上三种扫描路径（方形，直线加半圆形以及锯齿形）的误差函数的数学模型，分析了矩形测量面尺寸大小，扫描测量面到声源的距离等参数对扫描误差的影响，给出了恒定扫描程度条件下各扫描路径的误差函数曲线，研究表明：三种扫描路径均收敛于真值，且锯齿形收敛最快；扫描线密度应随着声源的复杂程度而加大；减小扫描路径间距会提高收敛精度；而增大扫描面尺寸不能提高收敛精度，但适当增大声源到扫描面的距离，可以提高收敛精度。

A Study on the Scanning Path Error for Determing Sound Power Level Using Sound Intensity Scanning

According to the ISO9614 2 standard, the monopole source, dipole source and quadrupole source are invastigeted, and the three kinds of error functions of scanning paths (i.e. rectangle path, linear integrated with half circle path, and hackle path) on a rectangle surface are developed. The influence of the area of the rectangle surface, as well as the distance between scanning surfaces and the sound source, to the scanning error are analyzed. The results show that these kinds of scanning paths are all convergence to real values, among which convergence speed of hackle is the fastest. Increasing the complexity of sound source, and decreasing the distance between scanning paths can improve the convergence precision. The density of scanning lines should increase with the complexity of the sound source,and the distance between scanning paths should decrease. The results also show that increasing the scanning area can not increase the convergence precision, but properly increasing the distance between the sound source and scanning surface can do.