|The Performance Assessment of Wave and Tidal Array Systems (PerAWaT) project, launched in October 2009 with £8m of ETI investment. The project delivered validated, commercial software tools capable of significantly reducing the levels of uncertainty associated with predicting the energy yield of major wave and tidal stream energy arrays. It also produced information that will help reduce commercial risk of future large scale wave and tidal array developments.
The purpose of the experiments of work package WG4WP2 is to investigate the hydrodynamic interactions of rotors when operating within arrays. Specifically the objectives of WG4WP2 were: to investigate the influence of bounding surfaces (free surface, seabed and other devices) on device performance and loading; to analysis the effect of the bounding surfaces, ambient flow field and device performance characteristicson the far wake form; and, to investigate wake interactions within an array under varying ambient conditions (seabed, waves and large eddies).
To achieve the set objectives a series of small-scale experiments of arrays of tidal stream turbine rotors were conducted in a wide channel. The tests were conducted at approximately 1:70th geometric scale using rotors that are specifically designed to produce similar momentum extraction to a generic full-scale rotor design. The experimental facility used enables the layout of various array configurations to be investigated along with different ambient flow conditions including surface waves, added seabed roughness and a large upstream island.
This deliverable, the final deliverable in WG4 WP2 presents a summary of the results of the University of Manchester experimental programme – investigating tidal arrays (up to15 devices in an array). A detailed test description is presented and methodologies of data acquisition and post processing are described. A description of the database of results is presented to enable the reader to interpret the raw data. The key findings of the experimental testing programme are discussed and it is confirmed that the final test schedule meets the requirements specified in WG4 WP2 D1