Wind Farm Aerodynamics: CFD

In order to obtain a deeper understanding of the flow inside wind farms, a full 3D unsteady Navier-Stokes solver is developed. One of the primary concerns in this development is the ability of the solver to simulate turbulent wakes over long distances. Since the correct simulation of turbulence is of utmost importance to discover the mechanisms of mixing and wake decay, we are considering the use of Large Eddy Simulation (LES) models as the best compromise between accuracy and computational cost. In combination with high-order energy-preserving discretization schemes we believe that this is a physically and mathematically sound way to obtain realistic wind turbine wake simulations.

At the same time, commercial software like ANSYS CFX is used to investigate the accuracy of 'virtual blade' or 'actuator disc' models as compared to full wind turbine blade models. Such actuator disc models are necessary in the simulation of wind farms, and CFX is a useful tool to improve and finetune them.

Publications

Aerodynamics of wind turbine wakes
Sanderse, B.
ECN-E--09-016  april 2009