SENSITIVITY OF WAKE LOSSES TO WIND TURBINE DIAMETER FOR AN OFFSHORE WIND FARM

摘要

The power production loss due to wakes is one of the main sources of energy losses in large offshore wind farms. These wake losses are dependent on a number of factors, including the rotor diameter, layout configuration, performance of the turbines as a function of speed and the climatology at the site. The aim of the current study is to quantify the effect of increasing the rotor diameter in terms of yield losses due to wakes. The wake losses are simulated with ANSYS' WindModeller, a CFD tool which uses an actuator disk model to estimate the wake losses. To keep CPU time tractable, an approach is devised to reduce the number of required CFD simulations, without compromising on the prediction accuracy. Three turbines types with identical rated power but different rotor sizes are considered for the same wind farm layout. The sensitivity of the wake losses to surface stability conditions is also investigated for some specific cases.