Coordinateurs du projet
Context
The objective of the ECOSFARM project is to develop a generic numerical simulation tool for evaluating control strategies for fixed and floating offshore wind farms and tidal turbine farms. This tool, which adopts a relatively detailed description of the physics of flows and turbines, will be used in the advanced design phase to verify and refine the preliminary farm designs established upstream. For example, for a given turbine layout, it will enable the evaluation and improvement of planned control strategies before their integration into actual offshore farms, and confirm the correct layout of the turbines at the installation site.
Scientific breakthroughs and innovation
- There is currently no specific tool capable of evaluating control strategies for fixed or floating tidal turbine farms, so this project will enable us to take the lead in this area.
- There is also no farm-scale tool for simulating floating wind farms and evaluating their control strategies (the goal is to have a mature tool within five years).
- The accuracy of the fluid solver used in this tool is superior to that used in the state of the art (e.g., SOWFA).
Expected technical and economic impact
- Provide a decision-making tool for companies wishing to optimize the control strategy for their wind or tidal farms.
- Promote the consideration of control in wind and tidal energy research projects
- The ECOSFARM project will provide D-ICE with a tool to evaluate the controllers they develop before installing them in real-world offshore conditions, thereby improving the quality of the services they offer. This technological building block will enable them to strengthen their recent positioning in the wind power sector and extend it to the tidal power sector.
Results
VALIDATION OF THE WCCH-FAST COUPLING ON THE NREL 5MW WIND TURBINE
This figure compares the results obtained using the WCCH-FAST coupling with the results obtained using FAST alone. With this in mind, we look at four gauges positioned along a blade that allow us to monitor the forces along a blade (Fx, Fy), the blade pitch angle (β), the wind turbine rotation speed (Ω), the rotor torque (Trot), and the power generated by the turbine (Pgen).
PHYSICS CAPTURED BY WCCH-FAST
This figure shows the tip and root vortices and some 3D effects captured by WCCH-FAST. In the bottom left photo, the black arrows show the tip and root vortices generated by the coupling. These vortices are caused by shear stresses at these locations and are typical of rotors.
In the other two images, we can see the 3D effects occurring on the blades. Coupling CFD with a Blade Element Method allows us to overcome the independence condition between blade elements in BEMT models and thus better represent the physics.
APPLICATION OF WCCH-FAST COUPLING TO THE CASE OF TWO ALIGNED TURBINES
The experimental case selected for validating the WCCH-FAST coupling is “Blindtest 2,” described and discussed in Pierella et al. 2014. This case presents a configuration where two wind turbines are placed in line in a wind tunnel.
The figure below shows a comparison of the numerical and experimental deficits in mean axial velocity at locations 1D, 2.5D, and 4D in the wake downstream of the second turbine (left), as well as a snapshot of the mean axial velocity contour iso-vorticities obtained by the simulation (right). The numerical results obtained are generally in good agreement with the experimental signals, particularly in the far wake of the wind turbine, highlighting the ability of the proposed coupling to simulate wind farms.
