ACOUSTIC ANALYSIS AND MEASUREMENTS OF MEGA YACHTS DURING CONSTRUCTION

Abstract

Noise is a critical parameter for super/mega yachts which can be verified only in the final stage of a mega yacht building project. Although there are more and more advanced methods to predict noise prior to the sea trials, verification has to be delayed until the noise survey is conducted during the sea trial. A new methodology is proposed based on measurements during construction to determine the transmission losses of both airborne and structure borne noise and propagation of the sound from the source to the receiver using these measurements. A 66 meter mega yacht case study is presented with measurements of airborne noise emitted through an omni-directional dodecahedron loudspeaker and measurements of structure borne noise generated by a tapping device. Both sound pressure levels and vibrations are measured to derive the transmission losses. A source-path-receiver method-based prediction tool, SNoPP, is employed to project the measurements into the final noise predictions. Comparisons between the measurements and the predictions are also presented.