Severe wind turbine blade leading-edge surface erosion can cause increased wind turbine performance losses that are far greater than anticipated during wind power plant development.

“For many wind plants, leading-edge erosion is the largest source of maintenance costs for blades,” says Josh Paquette, who leads Sandia National Laboratories’ Blade Reliability Collaborative. Sandia’s leading-edge erosion research project team recently completed several project phases, uncovering several effects of blade erosion and roughness—including a potential reduction of annual energy production of more than 5% for a utility-scale wind turbine. The experimental data and roughness model generated as part of this project will be used to reduce the uncertainty of the impact of leading-edge erosion on wind power plant performance predictions, optimize blade maintenance cycles, and develop more robust blade designs.

Researchers used a profilometer to measure blade surface roughness and erosion at an operational utility-scale wind farm during the project’s first phase of work. A computational model, developed with partners at University of California Davis, captured the effect of roughness and erosion on airfoil transition and performance characteristics.

In the second phase of the research, the research team compared the model results to the experimental results of the S814 airfoil from the Texas A&M Oran W. Nicks Low Speed Wind Tunnel, which established the model’s reliability for tip and midspan airfoils. An airfoil with nominal field roughness performs better than an airfoil with transition tape, often used in airfoil experiments to force airflow transition to occur abruptly near the blade’s leading edge.

The reports and associated data will be released in early June through the Atmosphere to Electrons (A2e) Data Archive and Portal.