||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.
This document outlines the issues associated with modelling a region of the wake behind a tidal turbine rotor, known as the near wake or the beginning of the far wake region.
- A review of the existing literature is presented which provides an overview of both the applicable modelling options and previous experimental campaigns which characterise the wake region of interest.
- The GH near wake model is described and the modelling approach justified.
- The model is used to predict the three dimensional flow field which is then passed to the GH far wake model as an input.
- The GH Blockage model feeds the model when appropriate, providing a corrected rotor thrust and an altered flow field around the turbine.
- A list of key assumptions that the GH near wake model makes is provided along with the relevant references to existing theory.
- The method by which the mathematical models are implemented intoa working code is described, as is the way in which the GH near wake model is to be incorporated within the GH TidalFarmer Beta code.
- Flow diagrams of the GH near wake model algorithms are presented and example outputs provided