Extreme wind and wave loads on the next generation of offshore wind turbines

Lead Research Organisation: University of Oxford
Department Name: Engineering Science

Abstract

In many areas around the world dominant load on offshore wind turbines is from environmental forces. One example of this is in China where typhoons can do considerable damage to offshore installations. This project builds up from fundamental modelling of the underlying environment and how offshore wind turbines interact with this, to analyzing the structural response and design scenarios.
The project will have four themes: The first stage examines the wave environment in areas of moderate depth and complex bathymetry with wind input. The second and third stages of the project will analyse loads from wind and waves on offshore wind structures. The fourth stage will examine the associated structural and geotechnical design. An ongoing theme throughout the project will be directed towards outreach, networking and dissemination. The project will improve our understanding of the underlying physical processes as well as exploring the design and environmental implications. In particular, the first theme will provide a better fundamental understanding of typhoon-wave interactions, an important topic in its own right in ocean environmental science.
The project will use a wide-range of techniques to tackle the particular problems. These range from analytical modelling of the underlying equations, numerical modelling, physical modelling, and analysis of field data. Insight from all these approaches will be pooled to tackle the challenge of designing offshore wind turbines in harsh maritime environments.

Planned Impact

This project addresses one of the key problems in the design of offshore wind turbines. By improving our understanding of loads on offshore wind turbines we can reduce the cost, uncertainty and risk of the technology. This work will tackle some fundamental challenges in ocean engineering and use the insight from this to improve the design of offshore wind structures. The methods and data sets produced will be made available to users in industry and academia and will be directly useable for design and research purposes.
 
Description i) We have explained a phenomena discovered about 10 years ago as to why you get rogue waves at the top of slopes. This is of significance to offshore wind turbines (particularly in China) as they are often located as far from shore as there is shallow water. We developed the theory analytically in Oxford. It was tested numerically in collaboration with China and experimentally in collaboration with othe UK/China ORE partners. Major papers are in preparation.
ii) We have extended a methodology we developed for calculating the higher harmonics of forces on offshore wind turbines to the calculation of moments. This was done experimentally in Oxford and in collaboration experimentally with ours. Papers are in review.
iii) We have examined the evolution of rogue wave density from initially non-equilibrium sea states experimental (in Shanghai) and numerically. A major paper is under review.
Exploitation Route This work can be used to improve load models for offshore wind turbines. We are working on ways of making this easy for users to use.
Sectors Energy

 
Description Meetng of UK/China ORE projects in Oxford 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Industry/Business
Results and Impact Meeting between all funded projects in the UK/China ORE consortium.
Year(s) Of Engagement Activity 2018
URL https://www.ukchn-core.com/event/kick%e2%80%90off-event-oxford-march-2018/
 
Description Meetng of UK/China ORE projects in Oxford 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact Join networking event for UK/China ORE funded projects.
Year(s) Of Engagement Activity 2019
URL https://www.ukchn-core.com/event/uk-china-joint-offshore-renewable-energy-conference-7th-to-10th-jul...
 
Description SupergenWind meeting 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Professional Practitioners
Results and Impact Dessiminate project to Supergen Wind meeting in Dundee
Year(s) Of Engagement Activity 2018