The Development And Correction Of Acoustic Intensity Measurement Based On Labview

The superiority of directional sound intensity is reflected in the modern acoustic measurement,sound intensity measurement does not require a specific anechoic chamber or hemi-anechoic chamber.With the development of sound intensity technology and test software and hardware,sound intensity measurement has been widely used in the field of sound power measurement, noise source identification, sound field characteristic analysis and so on.The application of sound intensity technology can not be separated from precise testing system,As traditional sound intensity measurement is expensive, probe interval limits the test frequency domain because of the finite difference error, wideband noise needs several tests.This paper using virtual instrument technology which developed in recent years,a convenient,efficient and inexpensive sound intensity measurement system based on the modified cross-spectrum sound intensity method is developed.This paper is divided into five parts,the first,described the current research status of sound intensity technology and the purpose and significance of the topic;the second,introduced the theoretical basis of sound intensity measurement;the third, Analyzed the error and correction method of cross-spectrum sound intensity;the forth, introduced the core algorithm module of the sound intensity measurement system;the fifth,verified the effectiveness of the system and the theoretical analysis results by using the combination of simulation test and field test. The experimental results show that,no matter before and after correction,the measurement error of this sound intensity measurement system is controlled within the 1dB in the test frequency band that corresponds the probe interval,meet the requirements of most engineering test,for the same probe interval,testing frequency domain of modified system is expanded and modified system is more precise.