Abstract
The considerable increase of wind turbine rotor size and weight in the last years has made impossible to control as they were controlled 20 years ago. The cost of energy is an essential role to maintain this type of energy as a viable alternative in economic terms with traditional or other renewable energies. Through the last decades many different flow control devices have been developed. Most of them were shaped for aeronautical issues and this was its first research application. Currently researchers are working to optimize and introduce these types of devices in multi megawatt wind turbines. Gurney flap (GF) is a vane perpendicular to the airfoil surface with a size between 0.1 and 3% of the airfoil chord length, placed in the lower or upper side of the airfoil close to the trailing edge of the airfoil. When GFs are appropriately designed, they increase the total lift of the airfoil while reducing the drag. Thanks to the implementation of the of this flow control device the efficiency of a wind turbine improves, which results on an increase in the power generation.
Highlights
In the last fifteen years, it has been a considerable growth in the installation of wind power in Europe
At lower average wind speeds of NTM5 (Normal Turbulence Model with averaged speed of 5 m/s) the increment in the power output wanders around 10% for different passive devices configurations
That increase decays to 3% at 10 m/s (NTM10) of average wind velocity, which is still significant
Summary
In the last fifteen years, it has been a considerable growth in the installation of wind power in Europe. The rise in the average wind turbine power production was 10.4%, in comparison with the clean wind turbine at a wind speed of NTM5 and 3.5% at NTM10 This increase in offshore wind energy installations shows the relevance of research in the field of flow control for large wind turbines. Passive flow control devices generate an increase in the efficiency of the turbine and reduce load without additional energy consumption. Focusing on the flow control devices, the one which is going to be studied is the GF, that belongs to the passive control ones It consists on a ledge with a height between 0.1% and 3% of the airfoil chord length, located in the trailing edge of the airfoil and perpendicular to its lower or upper surface (Figure 1). To validate the CFD model with experimental data and secondly, to compare the CFD lift and drag coefficient (CD) results for two cases: a clean DU91(2)W250 airfoil and DU91(2)W250 with GF
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
