双传声器声强测量系统误差分析与不确定度评定

Error Analysis and Evaluation of Uncertainty of a Two-microphone Sound Intensity Measurement System

双传声器互谱声强测量法适用于现场测量机器的声功率和进行声源识别。为了提高测量精度 ,需要分析影响测量精度的各种因素 ,确定被测量值的估计值和分散性。从双传声器互谱法测量声强的原理及测量系统的配置出发 ,分析讨论了互谱声强测量中误差产生的原因及其影响声强测量精度的主要因素 ;对声强测量系统测量声强量值的不确定度进行了评估 ,并对评定结果进行了实验验证 ,评定结果与实际检测结果相符 ;

A measuring method for two microphone cross spectrum sound intensity suits for the determination of acoustical power of a machine and the identification of sound source on the spot. To enhance the measurement decision, various factors that influenced the measurement decision were analyzed and the estimated value and dispersivity of tested value were determined. According to the principle of the two microphone cross spectrum method for determining sound intensity and the collocation of measurement system, the cause of the error in measuring the cross spectrum sound intensity and the main factors influencing the measurement accuracy were discussed. The evaluation of the uncertainty of sound intensity with a sound intensity measurement system was made and validated by the experiments. The results from the evaluation and the experiments coincide well. Finally some possible approaches to reduce the main error of the sound intensity measurement system were given.