Wind Turbine Foundation Ultrasonic Spectral Characterisation (WINSPEC)

Lead Research Organisation: British Geological Survey
Department Name: Engineering Geology

Abstract

WINSPEC will study the feasibility and specification of a marine operated, low frequency modulated ultrasonic 'pulse-echo' method for monitoring the structure and condition of the layered foundations of offshore wind turbines. Numerical modelling and some laboratory testing will be undertaken to evaluate the sensitivity and characteristics of the spectral response to differing layered model representations of the foundation structure with various condition 'defects' built in. This work will provide experimental and modeled analyses to support a feasibility assessment of the 'pulse-echo' approach, where possible, identifying characteristic acoustic patterns (or signatures) that relate to varying the material properties of the layers and structure of the layered sequence, such as thickness and density and the introduction of inter-layer water. This work will be supported by E.ON Technologies (Ratcliffe) Ltd. who are responsible the maintenance of many of the UK's offshore wind farms such as Robin Rigg in the Solway Firth. These wind farms are national assets; for example Robin Rigg provides 180 MW of power to the National Grid (enough energy for over 100, 000 households). This method could form the basis for a safe, low power technology for deployment on underwater unmanned vehicles for inspecting the inner structure and condition of offshore wind turbine foundations. In so doing, WINSPEC would stimulate a shift towards improved asset inspection technologies supporting preventative interventions maintaining wind farm operation at higher generating capacities.
 
Description WINSPEC demonstrated the feasibility of the low frequency ultrasound method on engineered structures in a marine environment.
Exploitation Route WINSPEC provided the catalyst for the development of a potential routine commercial inspection service for monopile wind turbine foundation condition for which E.ON have filed a patent to protect foreground IP arising from the trials. Foundation condition information will have a major impact on offshore wind farm management because it will enable improved estimates of wind turbine life cycle and better prioritisation of retrofitted repairs.
Sectors Construction,Energy,Environment

 
Description WINSPEC involved numerical modelling and laboratory experimentation to evaluate the use of the spectral characteristics of ultrasonic echoes for diagnosing defects, such as water-filled cracks in wind turbine foundation structures. The main project outputs included: 1: Numerical models of the ultrasonic reflectivity of a foundation in good condition and with a range of potential defects, including cracks between the steel and concrete sub-structures. 2: A laboratory facility for handling and testing heavy samples whose structures resembled sections through monopile wind turbine foundations in good and defected conditions. 3: Laboratory test data showing spectral characteristics of echoes on proxy samples representing foundations in good and defected conditions. This led to two key outcomes, which were supported by †EON Technologies (Ratcliffe) Ltd., including the: 1: development and field testing of two ROV deployed prototype ultrasound inspection systems to TRL 5 and 6, and the 2. field testing of the second ROV deployed prototype to TRL 7 in wind turbines at the Robin Rigg wind farm, Solway Firth.
First Year Of Impact 2015
Sector Energy,Environment
Impact Types Societal,Economic

 
Description E.On New Build and Technology; Wind turbine inspection 
Organisation Uniper Technologies Limited
Country United Kingdom 
Sector Private 
PI Contribution 1. numercial modelling; 2. laboratory testing; 3. prototype design; 4. field prototype testing; 5. tests in operational environment
Collaborator Contribution access to materials suppliers, field and operational test sites. Journal and conference paper writing.
Impact CR Brett, DA Gunn, BAJ Dashwood, SJ Holyoake and PB Wilkinson. 2017. Development of a technique for inspecting the foundations of offshore wind turbines. NDT 2017. 56th An. Conf. BINDT, 5-7 Sept, Telford. CR Brett, DA Gunn, BAJ Dashwood, SJ Holyoake and PB Wilkinson. 2017. Development of a Technique for Inspecting the Foundations of Offshore Wind Turbines. WindEurope Conference & Exhibition, Amsterdam, 28-30 Nov, 2017. CR Brett, DA Gunn, BAJ Dashwood, SJ Holyoake and PB Wilkinson. 2018. The inspection of foundations in offshore wind turbines. Insight - the Journal of the British Institute of NDT. V60, N1, 19-27.
Start Year 2012