Objectives and problems to be solved:
The objectives of the project are to fill in important knowledge gaps connected to the wind turbine blade design process and develop the necessary design tools. Traditional tools used in the wind turbine industry are unable to handle various fundamental flow problems. It is believed that one feasible path to obtain the missing knowledge is through development and application of tools based on Navier-Stokes solvers (NS solvers). The goals are to provide industry with applicable knowledge and methods based on NS solvers that will allow manufacturing of more optimal, stable and cost effective wind turbine blades. There is a strong confidence within the consortium, based upon recent verification studies that a series of unsolved aerodynamic and aero elastic problems within the wind energy community can be addressed successfully using NS solvers.
Description of work:
Four very important issues will be treated in the present project, with activities split in five technical work packages.
The topics are the following:
- Improving the power prediction capability of existing state of the art 3D Navier-Stokes solvers, by including models for the laminar/turbulent transition process, and using advanced turbulence models. Especially for stall controlled wind turbines, this will allow for a much more optimised blade design, because the power production, blade loading and the stall behaviour can be predicted more accurately.
- Models for aerodynamic accessories used by wind turbine industry, as vortex generators, stall-strips, zigzag tape etc will be developed, and implemented in the existing Navier-Stokes solvers. Additionally numerical simulations of active flow control concepts, such as pulsating jets, will be carried out. This will allow wind turbine blade manufactures to incorporate aerodynamic accessories already during the design phase, and not only as means of repairing bad aerodynamics of already existing blades
- The 2D Navier-Stokes based aero elastic tools developed in previous projects, will be extended to deal with full 3D aero elastic blade problems. The tools will be based on existing 2D/quasi-3D and full 3D Navier-Stokes solvers and 3D beam element structural models. The models will allow computation of the aerodynamic damping characteristics of actual wind turbine blades. Additionally the existing 2D aero elastic tools will be used to investigate the aerodynamic damping properties of airfoil sections equipped with aerodynamic accessories.
- Finally some industrial flow details of great importance will be investigated using NS-solvers: Tip-shapes and loads under stand still conditions. The project will in addition advance the simulation capacity of the European wind turbine industry, while providing at the same time an aerodynamic/aero elastic database on a series of important cases relevant for the wind turbine design process.
Important milestones are the implementation of 3D laminar/turbulent transition models, development of models for aerodynamic accessories, and the development of quasi-3D and full 3D NS-aero elastic codes. This will allow more accurate prediction of power curves, and blade aerodynamic damping characteristics.
Funding SchemeCSC - Cost-sharing contracts
19009 Raphina (Pikeermi)
172 90 Stockholm