WindDyS research project

Project title: WindDyS – Development and investigation of a novel dynamic stall model for the preliminary design of wind turbine rotor blades

Objective and reason for the project:

The WindDyS project investigated the dynamic behavior of aerodynamic cross-section profiles of rotor blades for wind turbines. If the angle of attack over which the airfoils are approached is changed dynamically, this can lead to a change in behavior in the area of the stall – the so-called dynamic stall. The WindDyS project has been concerned with simulating this behavior precisely with numerical flow calculations and developing a reliable model with which these calculations can be transferred to industrial load calculations. Until now, adapted models originally developed for helicopter aerodynamics have been used for this purpose. The aim of the project is to use an improved wind energy-specific model to promote the development of longer, lighter and thus also more flexible rotor blades in order to enable the construction of fewer but larger wind turbines in the future and thus conserve the resources required for the energy transition.

Methods and work steps

In the project, extensive numerical flow simulations were carried out for various profile geometries, especially thick ones, which depict their properties under different conditions. The results of the high-resolution flow simulations should be used to create an improved model for the occurrence of dynamic stall on wind energy profiles. Based on the Onera model, an approach was implemented which, with corrections to the Onera model, allows the results of such calculations to be mapped in a simplified and fast model. This provides a necessary second-order approach for mapping the dynamic properties of the dynamic stall. Implementing the second-order model in the open source software OpenFAST requires significant adjustments to the core code, which can be implemented together with the code developer in the future.