Modelling Marine Renewable Energy Devices; Designing for Survivability

Completed

Renewable Energy Sources(Ocean Energy)

Basic and strategic applied research

PHYSICAL SCIENCES AND MATHEMATICS (Applied Mathematics)
ENGINEERING AND TECHNOLOGY (Civil Engineering)
ENVIRONMENTAL SCIENCES (Earth Systems and Environmental Sciences)

Not Cross-cutting

Professor C Swan
Civil and Environmental Eng
Imperial College London

Standard

EPSRC

30 June 2012

29 December 2015

42 months

£1,039,617

Energy

London

Energy : Energy

Professor C Swan, Civil and Environmental Eng, Imperial College London

Professor DM Causon, Computing and Mathematics, Manchester Metropolitan University
Mr C Mingham, Computing and Mathematics, Manchester Metropolitan University
Dr L Qian, Computing and Mathematics, Manchester Metropolitan University
Dr J Spinneken, Civil and Environmental Eng, Imperial College London
Professor T Whittaker, Planning, Architecture and Civil Engineering, Queen's University Belfast

Dr M Folley, Planning, Architecture and Civil Engineering, Queen's University Belfast

Project Contact, DET Norske Veritas As, Norway
Project Contact, Aquamarine Power Ltd
Project Contact, Wavebob Ltd, Ireland
Project Contact, Sabah Shell Petroleum Co. Ltd., Malaysia
Project Contact, Garrad Hassan and Partners Ltd

The primary aim of the project is the assessment of the extreme wave loads on WECs using numerical models validated against experimental observations and full-scale prototype data. The project team combines institutions with significant experience in research into extreme waves (Imperial College), wave energy converters (Queen's University Belfast) and numerical modelling (Manchester Metropolitan University), forming a strong and well-balanced consortium. They will be supported by a steering committee comprising a number of key industrial practitioners and stakeholders, bringing in a wide range of backgrounds from device developers, certifying bodies and the offshore industry.In designing wave energy converters (WECs), scientists and engineers face the challenge of having to compromise between two competing criteria. The power take-off, with all associated mechanical and electrical components having to be optimised for an annual average or nominal sea state. At the same time all these components will have to withstand large storm events, where the applied fluid loads are substantially higher compared to the nominal sea state. A successful design is inevitably characterised by one that balances these two criteria. Identifying such a balance at an early design stage (prior to expensive small or large scale physical model testing) requires accurate, reliable and efficient numerical models appropriate to both design criteria. Survivability defines the long term success of a WEC, and must be addressed by design.Water waves exhibit inherent nonlinearities, which are functions of the wave steepness. In severe sea states, linear models fail to predict the fluid kinematics. As a result, the numerical modelling of wave loading in severe sea states is challenging; the loads being directly affected by the underlying fluid kinematics. Further, the occurrences of wave impacts, wave breaking and air entrainment pose additional challenges. An accurate description of wave nonlinearities, combined with the ability to model local loading effects, is key to the success of the numerical modelling. The project team brings in world-leading expertise in the development of numerical models. In fact, these models have now reached a level of sophistication where a direct comparison with experimental data is practical.The integrated research programme builds upon(i) The latest advances in Met-Ocean, providing a realistic input to both the numerical and the experimental modelling(ii) Numerical modelling based on a hierarchical approach, ranging from linear and fully nonlinear potential flow models to fully nonlinear viscous flow solvers(iii) Extensive experimental investigation using state-of-the-art wave testing facilities appropriate to both shallow and intermediate / deep water conditions(iv) Comparisons with field data relating to loading of prototype WECsThe results of the numerical models will be analysed to provide guidance on the appropriateness of particular models, as well as issues associated with the scaling of extreme loads. This will enable an estimation of the uncertainty in extreme loads based on the modelling technique adopted. The research programme initially focuses on two generic device types, and guidelines for the application of the models to other WECs will be developed. In summary, the project is defined by a twin-track approach, combining advanced numerical models and careful experimental practice; the results of which will help to facilitate the large-scale deployment of wave energy converters

19/12/11