Analysis of methods for converting mechanical equipment manufacturers' sound pressure spectra to sound power spectra

To accurately predict mechanical noise levels, obtaining mechanical unit sound power spectra is critical. However, some mechanical equipment manufacturers only publish sound pressure level data. Furthermore, the measurement standards ISO 3745 and JIS 8616, used by many international HVAC equipment providers (e.g., LG, Daikin, Mitsubishi), combine radiated, inlet, and discharge noise into a single dataset. It becomes necessary to determine the sound power level for each path (i.e., discharge, inlet, and radiated) from this single set of sound data. As a result, sound pressure-to-power conversion methods can frequently yield inaccurate results. A more robust calculation procedure is required to increase the precision of the sound pressure to sound power conversion. This study focuses on the methods used to estimate sound power spectra from international HVAC manufacturer-provided sound pressure levels by applying acoustic principles and standards. This presentation discusses the development process of these tools, the theoretical basis of the conversion method, and the validation results.