充水阻抗管中测量材料声学性能的校准方法研究

提出了一种在充水阻抗管中,应用传递函数测量材料声学性能的三参数校准方法。在双传感器传递函数法的基础上,考虑充水阻抗管中水听器间不一致性和管内结构对声场局部扰动等因素的校准,导出了三个综合的无量纲校准参数。通过改变充水阻抗管中测量面的三个已知反射系数,测量出对应的三个传递函数,可以求出这三个校准参数。在充水阻抗管中分别对水/空气界面和一种水声材料进行了测量试验,应用该方法对测量结果的进行了校准,并对校准前后的结果进行了分析比较。

Calibration method in measurements of acoustic characteristics of materials in a water filled impedance tube

A three-parameter calibration method are presented in measurements of acoustic characteristics of mate-rials in a water filled impedance tube using transfer functions. Based on two-sensor transfer function method, three dimensionless calibration parameters are derived to calibrate the variance between the two hydrophones and the local perturbation of small structures in the tube, etc. These calibration parameters can be figured out by measuring the three transfer functions of three different but known reflection coefficients of the measurement plane in the water filled impedance tube. The acoustic characteristics of the water/air interface and a kind of underwater material are measured respectively in the water filled impedance tube. The measurement results are compared before and after using the calibration method.