In the determination of sound power level of a big sized machinery, sound intensity measurements can be carried out according to the international standard ISO 9614-2: 1996 – “Acoustics – Determination of sound power levels of noise sources using sound intensity. Part 2: Measurement by scanning”. Some problems often occur if the intensity tests take place in environments with high not stationary background noise. To solve these problems, the standard ISO 9614 recommends using noise barriers to protect the test area from background noise. About the barriers to be used, the standard gives only general suggestions. Another main problem arises during intensity tests when barriers do not protect the whole machine extension because of the high dimensions of the source. These criticalities have been explored and solved by the authors that have recently made a series of sound intensity measurement campaigns on big sized machineries.
Autori: Borchi, Goretti, Iannuzzi, Luzzi