CFD for Horizontal Axis Wind Turbines

Ph.D. student: Sugoi Gomez-Iradi

The analysis and design of wind turbines is a challenging task well beyond the capabilities of conventional engineering methods.
CFD analysis of wind turbines is at the edge of what commercial CFD packages can offer and this creates the opportunity for research into CFD methods that will allow engineers to simulate complete turbines at realistic conditions. The literature suggests that key problems in the CFD analysis of wind turbines are the difficulty in simulating the rotating blades taking into account the effect of the tower supporting the turbine and the difficulty in adequately modelling the structural response of blades of very large diameter. Other important effects include flow transition on the blades, modelling dynamic stall and 3D aerodynamic effects.  The lack of adequate sets of experimental data suitable for validation of simulation tools is also a problem.


The objective of this research is to develop a CFD method for the analysis of horizontal axis wind turbines (HAWT). Starting from conventional CFD methods, sliding planes will be introduced between CFD meshes fixed on the turbine blades and the support tower to account for the rotation of the blades. Several numerical issues need to be addressed, creating opportunities for exciting research in numerical methods and interpolation techniques, while not violating the conservation laws and maintaining the efficiency of the calculations. The sliding grids will also allow for modelling the relative motion of the blades and the ground.

 Moving to the structural analysis of the HAWT, modal analysis is the traditional way in which CFD solvers have been interfaced with Computational Structural Dynamics (CSD)  models.
 For this project, this approach will be taken one step further by implementing additional finite element models for the turbine blades based on beams which allow deflection and  torsion, which are suitable for high diameter blades.

To account for the low Reynolds number flow on parts of the blades and the transition from laminar to turbulent flow conditions, transition modelling is required.
Transition models already available in the literature will be implemented and this will allow better predictions for the aerodynamic forces on the blades.

For the validation of the simulation tool, two sets of data will be used. The first set corresponds to wind tunnel data  from the IEA Annex XX (Phase VI), which will be used for the validation of the CFD method. These data are free from atmospheric disturbances and correspond to an idealised case for wind turbines and have been used by many researches in the literature. The second set of data will be from a field data of an actual size wind turbine.

This Ph.D. is sponsored by CENER.

Formal contact: Dr. G. Barakos (supervisor)