Sound Intensity Measurements for Identifying Dominant Transmission Paths in Shipboard Partition Walls

The study focuses on two representative partition wall configurations: a long, lightweight cabin-to-cabin partition without sanitary units and a public space-to-cabin separation incorporating ventilation inlet and outlet elements. Sound intensity measurements were performed using a Microflown Scan & Paint 3D system, allowing spatially resolved mapping of sound energy flow through the separating structures.
The results show that, for long partition walls with limited structural stiffness, sound transmission is dominated by panel vibration over a large surface area rather than by localized defects. In contrast, for partitions connected to public spaces, the dominant transmission paths were found to be concentrated around ventilation elements, indicating locally dominant weak points despite otherwise adequate partition wall construction.
The measurements demonstrate how sound intensity techniques can effectively distinguish between globally radiating partition wall behaviour and locally leaking elements, which cannot be resolved using standardized insulation indices alone. The findings underline the importance of structural stiffness and detailing of service penetrations, such as ventilation inlets and outlets, in onboard acoustic design.
This work illustrates the added value of 3D sound intensity measurements for diagnosing sound transmission mechanisms in complex shipboard environments and supports their use for targeted design optimization and verification in shipboard acoustics.