In the oil & gas industry there is a trend towards more subsea activities. To improve gas recovery from existing and new fields at greater depths, the produced gas will be compressed, processed and transported via subsea templates and underwater networks (pipelines, flexible risers, etc.). Besides the huge consequences for the subsea installation itself (reliability, maintenance, etc.), it also has consequences for underwater wildlife through the underwater source vibrations leading to sound radiation. Regulations aimed at managing the impact of underwater sound on marine life have been put in place by different nations [e.g. 1,2]. Many offshore operations require an assessment of the potential impact of underwater noise on the environment, which requires knowledge of the sound transmitted by the subsea components.
Until now very little is known about the underwater source mechanisms, the acoustic strength of these underwater networks, the coupling of the emitted source sound to the surrounding medium and the impact of the sound on the underwater wildlife. The dynamic behavior of networks for compressing and transporting gas, and the translation into emitted noise into air are rather well understood. However, due to the presence of the water the dynamic behavior from such subsea installation is very different than in air. To predict the dynamic behavior, the presence of the water cannot be neglected and has to be taken into account.
This paper presents a simplified model for a subsea high speed turbo-compressor coupled to the KrakenC normal mode propagation model. With this combined model the noise at remote locations can be predicted and compared with the ambient noise and other anthropogenic noise sources such as for instance shipping, dredging and wind farm operation noise.