DNVGL, the world’s largest independent energy advisory and certification body, announced on Tuesday the launch of a new Joint Industry Project called COBRA intended to analyze damage and erosion caused to wind turbine blades from high-speed impacts of foreign objects such as raindrops.
The new Joint Industry Project will see DNV GL partner with ten commercial partners to develop a COmprehensive methodology for Blade Rain erosion Analysis — COBRA. Partners include Vestas, Siemens Gamesa Renewable Energy, LM Wind Power, Ørsted, Mankeweicz, Akzonobel, Aerox-CEU, Polytech, Hempel, and PPG, and will focus on investigating the damage caused to leading-edge wind turbine blades from the high-speed impacts of foreign objects such as raindrops in an effort to identify the best way to develop protection systems.
While rain erosion won’t cause structural damage to the blade, it can nevertheless cause significant damage to unprotected wind turbine blades over the life of a turbine due to degrading the aerodynamic performance of the blade, thus reducing the blade’s energy generation output.
“With the trend of building larger machines continuing, greater research is required to provide more protection for wind turbine blades against rain erosion,” explained Steffen Laustsen, Head of Blade Materials, Offshore Technology at Siemens Gamesa Renewable Energy. “The high blade tip velocities associated with large blades makes the impact of rain especially demanding. We look forward to collaborating with the Joint Industry Project partners across all industries to improve the quality and durability of future blade designs.”
“Increasing the performance of wind turbines and blades is crucial for the transition to a cleaner energy system,” added Rich Barnes, Executive Vice President Americas at DNV GL. “Erosion of blades is affecting the global wind industry. There is currently a lack of methods and design protection systems to prevent blade erosion, so it is vital to identify solutions and develop tools to tackle erosion problems. The COBRA Joint Industry Project will address these challenges and share knowledge to advance the understanding within the wind energy industry.”
The COBRA Joint Industry Project is aiming to provide a Recommended Practice for designing a protection system against rain erosion which is intended to be published in July 2020. The Project partners will be working to address the following technical issues:
-Identify and define relevant material properties for a protection system
-Develop and methodology to handle and derive design loads from rain data
-Develop a model to conduct raindrop impact analysis
-Develop a design methodology for leading edge protection systems
Companies and interested parties who want to be a part of the COBRA Joint Industry Project can still express their interest and join, subject to approval by the Steering Committee.