Full Stream Ahead To Tidal Turbine Assessments

QED are delighted to announce the appointment of Dr. Corey Badger. Her role maintains the sophisticated CFD numerical capabilities employed as part of the Subhub tidal platform design process. This uses High Performance Computing (HPC) capabilities which clusters all the high end workstations together to provide 32 core processor power with shared memory of 256GB enabling massive numerical models to run quickly providing tangible results on turbine performance within weeks rather than months. These capabilities are part of the companies ANSYS Fluent CFD package which offer state of the art modelling methods.

QED offers these capabilities and services to other companies working in the sector including turbine and project developers. This includes the performance characterisation of tidal turbines both with and without the Subhub tidal platform to assess the impact of the structure on their performance.

More recently the company has been working with Queens University Belfast (QUB) to assess the impact of Subhub on turbulence within the TTT3 project. This involves taking ‘as measured’ ADCP measurements and determine the turbulence content in it and applying turbulence factors to a numerical model of a rotating turbine in steady state condition that provides accurate general loading and performance data (Ct, Cq, Cp). The next stage is to run these models in a transient solution providing unsteady loading results of the turbine and Subhub.

CFD numerical model of the TTT3 turbines including ‘as measured’ turbulence and flow conditions used to predict the steady state performance characteristics and unsteady loading conditions.

There have been some interesting results to date and this work will be a large part of Corey’s role to validate the claims that Subhub has major performance and unsteady loading benefits on tidal turbines. Further claims of reducing the effect of tidal shear on seabed mounted devices and lessening the issue of turbulence and cross flows on the turbine blades by steering the flow into the turbines like stators of a pump jet.

Corey has also taken on the development of the company’s Tidal and Wave Energy Evaluation Tools (TWEET).  The main module of TWEET takes as measured or theoretical tidal harmonic models along with CFD/BEM performance data of the turbines and projects the energy generated from the inlet condition over a period of a year or the life of the project. Monte Carlo simulations can then be run from within TWEET to determine the economic viability of the project.

Monte Carlo simulations for the cost of the mass including fabricated mass and ballast mass.

The company has also started building its own GIS mapping tool to store and maintain site data including bathymetry, flow rates, positions of moorings, pictures and videos of seabed conditions and mammal, bird and fauna sightings for EIA studies.

Output from QEDs GIS mapping tool showing the position of the selected Subhub test sites at the QUB test centre along with flow data and bathymetry.

Corey brings new capabilities to the company having completed her Ph.D in multiphase flows using OpenFOAM, the open source CFD package. She has used the Edinburgh Parallel Processing Centre (EPCC) super computer to complete her Ph.D and now QED Naval have implemented Linux on a dedicated compute server to run OpenFOAM  capable of completing very large numerical calculations in excess of 10 million cells. Transferring these models over to the EPCC will provide fully validated results within days rather than weeks.