Fully Submerged Evolution of SeaGen for Exposed Open Deep Water Locations

The University of Edinburgh will work with the principal partner, Marine Current Turbines Ltd, to evaluate of their anticipated next generation tidal current turbine system. This system will consist of an array of turbines mounted upon a buoyant support structure, which can be fixed to the sea bed during operation, or floated to the surface for maintenance or inspection. At all times the buoyant support structure is connected by a rigid beam to a joint on the sea bed.Work by the University of Edinburgh will involve hydrodynamic analysis of the proposed system. This will involve tests conducted in the University of Edinburgh's curved wave tank. A small scale model will be evaluated for its response to wave loading, especially during its most vulnerable periods which will occur when the system is either floating on the sea surface for maintenance operations or in transition from its fixed sea bed mounted positions. The University of Edinburgh curved wave tank can be fitted with a system of nozzles to give a limited simulation of current effects and this may also be included within the tests, if required. Simultaneous scaling of wave and current action at small scale is highly problematic, however, and alternative approaches to incorporate loading from current, such as through the application of external forces and moments equivalent to those anticipated from currents, will be preferentially utilised. The tests will be used in support of optimising the response of the support to wave action during vulnerable periods in the operational cycle. Of particular concern is system stability when exposed to waves and currents during maintenance operations, when the system is not attached to the sea bed.The floating system will also be numerically modelled using a package such as WAMIT to further optimise the processes, using the results of the experimental analysis to inform the numerical process further.The University will provide a report on the issues influencing the effective behaviour of the floating support system, which draws upon both the experimental test programme and the mathematical analysis.