REMS Blog

24/07/18

I joined the 1st cohort of the Renewable Energy Marine Structures (REMS) Centre for Doctoral Training (CDT) in 2014. At that time there was a feeling of reserved optimism in the developing European offshore wind sector that the CAPEX and OPEX price would incrementally reduce over the subsequent years and as a result the industry would grow at a steady pace. Four years on, in 2018, and now offshore wind is a booming global industry, with tumbling costs resulting in zero-subsidy offshore wind farms becoming a reality.

As part of REMS, I am undertaking a DEng at the University of Oxford, while working at Fugro GB Marine Limited within the GeoConsultancy service line. My aim is to develop practical constitutive models for the numerical modelling of offshore foundations. I selected this as my topic area for research as, based on my time working as a geotechnical consultant on finite element analysis (FEA) projects, it was clear that there was a large gap between industry and academia. I felt the proposed DEng format within a CDT offered the perfect environment for this research to attempt to bridge the gap. Being part of the REMS CDT offers the opportunity to work at the interface between industry and academia in a highly dynamic exciting industry. A DEng is similar to a traditional DPhil (or PhD) in many ways, with the main difference being a practical industry tilt to the research and the opportunity to work on live industry projects. Some components of my DEng have involved development work for live offshore wind projects and others have involved more long term academic focused developments. In my opinion, this mix of academia and industry research offers a unique opportunity for short to medium term innovation within the industry. During the programme I have had many unique opportunities; including, spending 2 months at the University of Western Australia (UWA); undertaking a wide range of renewable energy focused doctorate level technical taught modules; applying my research on a number of commercial offshore wind projects; presenting at conferences and more academic focused research, steered by highly respected Professors from the University of Oxford.

A recent week of work for me in March 2018 within REMS is shown below which I think highlights the diverse opportunities available to me while undertaking my DEng within an engineering consultancy.

Monday:
My week starts at the Fugro office in Wallingford where, first thing in the morning, I attend a weekly design meeting for an offshore wind monopile foundation design project I have been working on. The consultancy project has been ongoing for 6 months and we are reaching the final stages. The project, which forms a section of my DEng portfolio, has been very challenging and has involved development of a number of new models and scripts to run and post-process a large number of 3D FEA. As part of the project we have some stress path tests running in the Fugro laboratory in Wallingford that are to be used for model calibration, so I spend some of my day checking the results completed so far to ensure they are as expected. The rest of my day is primarily spent running verification analyses for a new constitutive model I have implemented. I have been working on the model, termed the MSurf-ACE model, for many months with my supervisors, Prof. Chris Martin and Prof. Harvey Burd from the University of Oxford and Dr. Mike Rattley from Fugro.


Figure 1: Visiting the Fugro laboratory to inspect some ongoing stress path tests

Tuesday:
I am working from my office in the University of Oxford today where I am continuing to run verification analyses for the MSurf-ACE model. I manage to drag myself from the computer to take a break at lunch time and attend the weekly civil engineering seminar in the university.

Wednesday:
I spend Wednesday putting the finishing touches to slides I have prepared for a presentation I am to give in Holland for the Royal Netherlands Society of Engineers (KIVI). The presentation includes work from my research and additional recent innovations from the wider Fugro group.

Thursday:
I arrive in Holland and spend most of the day meeting colleagues at the Fugro office in Nootdorp to discuss innovation ideas across the Fugro group. In the evening I give my KIVI lecture titled: Foundation Optimisation for Ever Larger Turbines: Geotechnical Perspective. The lecture was attended by over 80 engineers and seemed to be well received, with several very interesting questions from the audience. I also had the opportunity to relax at the social event after the presentation and have some very interesting technical discussions with other engineers from the offshore industry.


Figure 2: Presentation at the KIVI lecture

Friday:
I arrive back in the UK early morning and go to the office to start preparing a draft journal paper to describe the new MSurf-ACE model I have been developing. I attend a meeting in the afternoon with my supervisors to discuss the structure of the planned journal paper and some recent results I have produced. After this I head for some much-needed rest!


Figure 3: Presenting results at a supervisory meeting
Scott Whyte
16/01/18

It is wise to start by welcoming the new cohort 2021 to the REMS centre and wish them loads of fun and success in their future researches. The week of the 18th of September was a particularly eventful for the REMS students. It was a week of conferences where both the annual REMS and the EAWE conferences were organised successively at Cranfield University. The sharing of knowledge and passions was demonstrated through various presentations which enabled a unique network to be established between both researchers and industry representatives. That said two REMS students had to leave the conference quite briskly as a result of their deployment for a field experiment. Those two students are Paul Causon and Waseem Khodabux who in the scope of their doctorate are analysing the marine growth effects and pitting corrosion on wind turbine foundation.

The weather displayed a certain kindness on those autumnal days of the 19th and 20th of September 2017. When such a small window of opportunity appears, it does make sense to take a leap. The van was booked waiting for the keys to be collected at the main reception for the adventure for our two protagonists, Waseem and Paul to begin. The destination was Bridlington also known as the lobster capital of Britain and which eventually has also transformed into a major port for offshore wind related projects due to its proximity to various windfarms on the east coast. In that area, quite a few windfarms going through different technological iterations from Round 1 to 3 have been installed. The colossal Dogger Bank also forms part of that cluster of offshore structures populating the seas around that region.

The anchors, plates, frames, ropes, cable ties and spacer were all loaded and it was time to hit the road. It turned out to be quite an impressive experience where Paul was describing the various hurdles that would have to be overcome once the pair were on the deployment boat. During the whole journey to Bridlington a plan was devised. When they reached the hotel they smiled. It had a Disco ball and it seemed the more mature generation were out partying in droves in the hotel. Unfortunately Paul and Waseem could not join the fun as there was work to do; instead they hit the road again to Tesco to gather some essentials for trial the next day.

It was already late by the time they returned to the hotel. They jumped into their respective beds and got up early at around 4am and directed themselves to the quay. The boat was a fishing one, sporting a crane of 500kgs lift capacity at the rear of it. They were welcomed by a small but experienced crew of researchers and the captain, loaded the experiment stuff and had a safety briefing by the captain of the boat.


Paul busy assembling the coupons and fine tuning the tying

The pair set off and as soon as they got familiar with the rocking motion of the waves set out to assemble the experiment. It involved the delicate task of tying the frames to the coupons and the buoys. A lot of rope cutting and cable ties tightening were needed but finally the task was complete. It was time to deploy the experiment. Moment of truth. The crane buzzed into life and the hook was hoisted down. Paul and Waseem retreated to the safety zone. There was the firm grip of the hook to the anchor and the operator manipulated the levers and soon the whole assembly was on the move. The anchor was released in the water first and seconds later, the whole assembly was sinking in the depth of the ocean. This was it, an experience to remember and cherish for a very long time. They cannot wait to go back for the full deployment but before then have to wait for a weather window.


Anchors going in the water Waseem posing

P.S. The trial assembly survived two storms and is still going strong.

Waseem Khodabux, Paul Causon
21/06/17
Offshore wind energy remains an untapped power resource in the United States of America considering the strong offshore wind power potential (of approx.. 4,150 GW according to NREL) along the US coasts, where major population centres are located. Due to slow wind speeds in regions with shallow waters located along the Gulf Coast and mid-Atlantic Coast, proven technology which is currently widely deployed in European shallow waters cannot be directly applied in the US. In contrary, US has significant potential in deep-water locations where floating offshore wind turbine structures are required.

Dr Todd Griffith from Sandia National Laboratories gave a prestige lecture on the 21st of April in Cranfield University providing an overview of the research projects currently taking place at Sandia National Laboratories addressing the unique conditions of the US offshore environment. Sandia is a US Federally Funded Research and Development Centre with the mission to deliver essential science and technology to address National Security challenges.


Figure 1 Snapshots from the Prestige Lecture given by Dr Todd Griffith from Sandia National Laboratories

Dr Griffith presented projects conducted by the Wind Energy Technologies Department of Sandia National Laboratories, covering:
  • Large-scale hurricane resilient wind turbine blade designs
  • Novel floating vertical axis wind turbines for deep-water siting
  • Offshore wind farm code development, and
  • Structural health monitoring & prognostics management systems.

Sandia has developed a series of detailed 100-meter blade reference models that are available to designers and researchers for design studies and cost analysis; while turbine models reaching 50 MW rated capacity using segmented ultralight morphing rotors based on bio-inspired load alignment (e.g. palm tree) have also been designed. The rotor’s load alignment reduces the required mass for blade stiffening, and makes the turbines more resistant to storms, while their segmented design allows the massive blades to be manufactured in segments which reduces the transportation and manufacturing costs.


Figure 2 Load alignment configuration. Source: Dr Todd Griffith’s presentation


Further research studies conducted at Sandia National Laboratories involve: Hi-resolution modeling of floating wind turbines, wherein a state of the art eddy simulation code has been formulated in order to simulate atmospheric turbulence with wind farms in both land-based and offshore environments; structural health and prognostics management with a focus on damage detection and analysis of effects of damage (state of health and remaining life), and floating offshore vertical-axis wind turbines, among others.



Figure 3 Results for Floating 13.2 MW Turbine. Source: Dr Todd Griffith’s presentation


Sandia has developed 6 public domain designs, covering a range of different areas: power performance models, structural models, economic models, anchor and mooring design, PTO design, O&M / Installation, permitting & environment.
Conclusively, this is an exciting time for marine renewables with significant growth prospects within the next decade. However, while there is the necessary technical know-how and proven technology is already deployed in European waters, as we move further from shore and as extreme scale wind turbines start to be deployed, conventional designs will no longer be applicable. Hence, innovative solutions focusing on reducing technology risks and cost of energy (COE) adjusted to location specific conditions need to be invented for different marine hydro-kinetic technologies.

More information on Sandia’s activities may be found here: http://energy.sandia.gov/energy/renewable-energy/wind-power/offshore-wind/

Author - Anastasia Ioannou