Acoustic intensity measurement instrument is a kind of instrument to measure the component of acoustic intensity in a certain direction in air medium. It can measure the acoustic power level of sound source by measuring the acoustic intensity in the field of the equipment. Meanwhile, it can also provide real-time frequency octave of sound intensity and sound pressure, 1/3 frequency spectrum analysis results, and acoustic intensity diagram, etc. The intensity distribution of sound energy flow in a plane near the sound source can be obtained through the multi-point acoustic intensity measurement to study the radiation characteristics of the sound source.

However, before determining which structural changes can properly reduce product radiative noise, the characteristics should be described according to the following aspects:

1. Spectrum composition

2. Location of main sound source

3. Relative importance of each main sound source

Noise source identification is a series of methods to complete the feature description.

Using the live sound intensity test,the position of the main sound source can be determined by moving the sound intersity probe on the surface of the object to be measured.This method can get the overall situation of the test object well,but it can’t quantify the"hot spot"and can’tprove the result well.

By demonstrating the radiation location and radiation level of the object under test, the intensity map can be used to identify the"hot spot"location of the noise radiation. Combining sound intensity clouds with spectrum analysis enables"hot spot"positioning of special frequency bands,such as finding harsh, pure sound components.

Based on the sound power of the cloud image, the radiation of the measured object as a whole, a specific structure, or a "hot spot" can be determined. Sorting can help determine how much each particular structure or "hot spot" contributes to total radiation, so that where changes can be made to get the best results.