Engineering Method of Sound Power Determination for Marine Engines

Sound power level evaluation methods for marine engines are investigated. Sound pressure based methods are discussed in this paper. In the highly reverbrant environment such as at engine room in a ship, precision of the sound pressure based methods tends to get worse.Through minute investigation on 10 test results, the authors introduce a new approach for the sound power evaluation in which mean level of PI index is used for environment correction factor. This approach, named the hybrid method, has both precision and practicality.