March 7 (Renewables Now) - Energy advisory and certification body DNV GL said Tuesday it has teamed up with 10 commercial partners to study the extent of wind turbine blade damage caused by raindrops and determine how best to develop protection systems.
Vestas Wind Systems, Siemens Gamesa Renewable Energy, LM Wind Power, Ørsted, Mankiewicz, Akzo Nobel, Aerox-CEU, Polytech, Hempel and PPG are DNV GL’s partners in the Comprehensive Methodology for Blade Rain Erosion Analysis, a project also known as COBRA.
“With the trend of building larger machines continuing, greater research is required to provide more protection for wind turbine blades against rain erosion. The high blade tip velocities associated with large blades makes the impact of rain especially demanding,” said Steffen Laustsen, Head of Blade Materials, Offshore Technology at Siemens Gamesa.
DNV GL explained that raindrops rarely affect the structural integrity of blades, but they can degrade their aerodynamic performance and thus reduce power generation over the life of a turbine.
The joint industry project aims to be ready by July 2020 with a Recommended Practice for designing a protection system against rain erosion. The partners will work to identify and define relevant material properties for a protection system, develop a methodology to handle and derive design loads from rain data, develop a model for raindrop impact analysis, and create a design methodology for leading edge protection systems.