Thesis defence Y. Zhang: wind turbines

14 June 2017 12:30 - Location: Aula, TU Delft - By: webredactie

Wind Turbine Rotor Aerodynamics - The IEA Mexico rotor explained. Promotor: Prof.dr. G.J.W. van Bussel (LR).

 

Wind turbines are operating under very complicated and uncontrolled environmental conditions, which causes large uncertainties of aerodynamic loads prediction in aerodynamic modelling. Such large discrepancies have been observed between experimental results and numerical predictions by different fidelities of aerodynamic models in the MEXICO experiment, where a three-bladed wind turbine rotor with 4.5 meters’ diameter has been comprehensively measured and investigated.

This doctoral dissertation aims to improve aerodynamic loads prediction by means of reducing the uncertainties of both numerical modelling and experimental measurement.  Firstly, an open source CFD code with high fidelity, OpenFOAM has been verified and validated especially for wind energy related application, some implementation errors in OpenFOAM -2.1.1 has been corrected and the improved model is further validated. Secondly, the non-rotating blades of the MEXICO rotor has been measured in the low-speed low turbulence wind tunnel under very well controlled conditions, in order to increase the fidelity of measured data. The 3D CFD simulation is performed to compared against experimental results and provide more insight to flow around the blades. The study indicates that the blades have complex design which causes 3D dominate rotor aerodynamics. Apart from that, the ZigZag strip plays a significant role in affecting the aerodynamic loads in the tip region. The ZigZag effects must be eliminated in the comparison of aerodynamic loads between CFD and measured data. Finally, a 3D simulation considering laminar-turbulent transition of the MEXICO rotor has been performed, and the numerical results show a very good agreement with the new experimental results which remove the ZigZag on the measured blades. More detailed of insight into the flow field around the wind turbine rotors (the MEXICO and TUDelft Blade 2) is also obtained in this dissertation. 

More information?
For access to theses by the PhD students you can have a look in TU Delft Repository, the digital storage of publications of TU Delft. Theses will be available within a few weeks after the actual thesis defence.