Performance and reliability testing of an active mooring system for peak load reduction
Proceedings of the Institution of Mechanical Engineers Part M: Journal of Engineering for the Maritime Environment
SAGE Publications / Professional Engineering Publishing (Institution of Mechanical Engineers)
© 2018 IMechE
Reason for embargo
Under embargo until 15 February 2019 in compliance with publisher policy
Offshore renewable energy systems are generally required to operate in exposed offshore locations for long deployment periods at low cost. This requires innovative new mooring system solutions to go beyond the existing offshore industry designs. A number of novel mooring systems have recently been proposed which decouple mooring line compliance and minimum breaking load, offering multiple benefits to designers. Demonstrating reliability for such highly novel systems where standards do not yet exist is a common problem both for mooring systems specifically and in offshore renewable applications generally. A performance and reliability test method is proposed here and is applied to a novel mooring system, the Intelligent Active Mooring System. The line stiffness and damping properties of Intelligent Active Mooring System can be optimised to the prevailing metocean conditions without compromising minimum breaking load; the pre-tension is also adjustable for tidal range compensation or for service access. The article presents the results of a feasibility study for Intelligent Active Mooring System including detailed, large-scale physical performance tests that demonstrate load reductions under normal operating and extreme sea state conditions. The rationale and findings for an accelerated reliability test regime that quantifies the ultimate load capacity of the component and gives insight into the governing failure modes are also presented. The presented test approach provides assurance for the overall system integrity.
The project was funded in part by the Technology Strategy Board (now Innovate UK) grant number 101970.
This is the author accepted manuscript. The final version is available from SAGE Publications via the DOI in this record
Vol. 232 (1), pp. 130 - 140