Towards Numerical Simulation of Offshore Wind Turbines Using Anisotropic Mesh Adaptation
In the context of reducing the cost of floating wind energy, predicting precisely the loads applied on structures and their response is essential. As the simulation of floating wind turbines requires the representation of both complex geometries and phenomena, several techniques have been developed. The wake generated by the aerodynamic loads experienced and the tower can be modeled using methodologies inherited from onshore wind simulation, and coupled with a hydrodynamic codes that were most of the time developed for the oil and gas industry. This work proposes a methodology for the simulation of a single or several turbines with an exact representation of the geometries involved, targeting an accurate evaluation of loads. The software library used is ICI-tech, developed at the High Performance Computing Institute (ICI) of Centrale Nantes. A single computational mesh is used, where every phase is defined through level-set functions. The Navier–Stokes (NS) equations are solved in the Variational MultiScale (VMS) formalism using finite element discretization and a monolithic approach. A coupling with an automatic and anisotropic adaptation procedure guarantees the good representation of the geometries immersed. The adaptation allows the simulation of phenomena with very different orders of magnitude, e.g. aerodynamics around blades and waves propagation. The reduction of the number of points in the mesh and the massive parallelization of the code are also necessary for wind turbine simulation.
KeywordsFloating wind turbines High performance computing Multiphase Navier–Stokes Anisotropic mesh adaptation
This work is funded by the WEAMEC (West Atlantic Marine Energy Community), and was performed by using HPC resources of the Centrale Nantes Supercomputing Centre on the cluster Liger and supported by a grant from the Institut de Calcul Intensif (ICI) under the project ID E1611150/2016.
- 2.Sebastian T, Lackner M (2011) Offshore floating wind turbines - an aerodynamic perspective. In: 49th AIAA aerospace sciences meeting including the new horizons forum and aerospace exposition, vol 720Google Scholar
- 6.Tran T-T, Kim D-H (2015) The platform pitching motion of floating offshore wind turbine: a preliminary unsteady aerodynamic analysis. JWEIA 142:65–81Google Scholar
- 9.Coupez T, Hachem E (2013) Solution of high-Re. incompressible flow with stabilized finite element and adaptive anisotropic meshing. CMAME 267:65–85Google Scholar
- 10.Digonnet H et al (2017) Massively parallel anisotropic mesh adaptation. IJHPCAGoogle Scholar
- 12.Lacaze, J.-B. et al. Small scale tests of floating wind turbines in the wind and wave flume of Luminy. 14th journées d’hydrodynamique, Val de Reuil, France, 18–20 Nov 2014Google Scholar
- 14.Bak C et al (2000) Wind tunnel tests of the NACA 63-415 and a modified NACA 63-415 airfoil. Forskningscenter Risoe, Risoe-R, Denmark, No. 1193Google Scholar