Session: New & Innovative FOW Design

Paper Number: 165119

165119 - Characterization & Modelling of the Wake of a Disruptive Floating Vawt for Yield Assessment 

Abstract: 

Offshore wind farm production is strongly impacted by turbine interaction effects (also referred to as wake and blockage effects). These effects extend over long distances over the ocean due to the lack of topology and surface roughness of the sea. As a consequence, the production for clustered projects will be lower than projects built in isolation. The capability to properly assess wake effect in tender phase appears then key to properly assess the economics of the project. To date, developers considered tools based on empirical and analytical model which have been calibrated thanks to small scale tests but for which limitations remain well known to the extent that this topic remains of first interest within the community.

The paper presents the results obtained through the development of an innovative and disruptive floating VAWT concept. It focusses on both experimental and numerical approaches launched within purpose to characterize the wake of the VAWT concept and calibrate numerical model (CFD based and analytical based model) to be further considered for Offshore Wind Farm Yield assessment.

The model tests performed in the basin facilities operated by Ifremer (Boulogne-sur-mer) have allowed to finely characterize the wake of the VAWT thanks to PIV and LDV measurements. They have highlighted the resorption mechanisms which take place in VAWT wake and that considerably reduced turbine wake compared to HAWT concepts. The results underline the impact of the turbulent boundary layer on the wake characteristics as well as the incoming turbulence rate.

Based on this exhaustive experimental database, numerical tools have been considered for benchmarking (CFD based model) and calibration (analytical based model). In that context, CFD-ALM model showed strong potential for wake & yield characterization and assessment that can be used conjointly with empirical based model for project developments. In parallel, the adaptation and calibration of the analytical Ouro-Lazennec model offer strong capabilities for front end developments and yield assessment allowing optimizing farm configuration depending on annual wind conditions and production maximization.

The paper finally concludes by outlining future developments (including experiments and numerical modelling), particularly considering the wake characterization in multiple VAWT configuration.

References :

Rosado Hau Nidiana, Augier Benoit, Paillard Benoit, Trasch Martin, Matoug Camil (2023). The assessment of a fast computational method in predicting the unsteady loads of vertical axis wind turbines undergoing floating motion . Journal Of Wind Engineering And Industrial Aerodynamics , 240, 105449 (14p.)

Querat Simon, Trasch Martin, Augier Benoit, Perier Vincent, Minguez M., Delon A., Barre S. (2025). Multi-scale study of a vertical axis wind turbine wake . In Innovations in Renewable Energies Offshore. Proceedings of the 6th International Conference on Renewable Energies Offshore (RENEW 2024, 19-21 November 2024, Lisbon, Portugal). 2025

Pablo Ouro, Maxime Lazennec. Theoretical modelling of the three-dimensional wake of vertical axis turbines. Flow. 2021

Presenting Author: Simon Querat Ifremer

Presenting Author Biography: I'm a PhD student at BlueTwin, based at the Marine Hydrodynamic Laboratory of Ifremer in Brest. My subject is the multi-scale experimental study of the wake of vertical wind turbines. During my thesis, I'm carrying out experimental campaigns in a flume tank, as well as on-site test campaigns. The aim is to understand the influence of the test parameters on the wake, in order to enable better extrapolation of the small-scale tests to the full scale. Before this thesis, I did a master's degree in fluid mechanics applied to the naval environment.

Authors:

Antoine Delon Bluetwin
Simon Querat Ifremer
Benoit Augier Ifremer
Stéphane Barre LEGI-CNRS
Guillaume Maurice Hydroquest
Matthieu Minguez Bluetwin