||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 report explains the data required from experimental study of an array of tidal stream devices. Issues associated with scale of the experiments are discussed and an appropriate facility is identified in the form of the University of Manchester wide flume. This facility allows conduct of experiments at approximately 1:70th geometric scale which will provide the specified data concerning the effect of turbine spacing and ambient flow on wake structure and device loading. Topics covered include
Engineering drawings are supplied for the main items of equipment. An explanation is given of how each of the required flow conditions – including steady flow with low turbulence intensity, steady flow with waves and increased levels of turbulence intensity and large scale eddies – will be generated. Although some aspects of equipment design may have been modified following preliminary manufacture and testing the equipment detailed represents the most suitable design choices at the time of writing. Following explanation of the experimental equipment, a brief outline is given of ongoing work at the time of writing.
- the generation of ambient flow conditions,
- method of measurement of time-varying flow- and mechanical parameters,
- design of small-scale model of a tidal stream turbine and
- design of a rotor suitable for the low Reynolds number of these experiments.