Production loss due to Leading Edge Erosion (LEE) of wind turbine blades is hard to quantify as erosion develops continuously, and the damage geometry differs for each blade. Having reliable prediction tools, e.g., based on Computational Fluid Dynamics (CFD), would allow wind turbine operators to optimise the blade maintenance schedule. However, CFD models have limited numerical resolution and can not resolve the smallest LEE damages; they must treat them as roughness. Therefore, Castorrini, Ortolani, and Campobasso (2023) ask:

Is the production loss from LEE mainly caused by large localised damages or small-scale surface roughness?

Castorrini, Ortolani, and Campobasso (2023) use CFD simulations of damaged airfoils to calculate the wind turbine production loss. The CFD is set up such that the large-scale LEE geometry is resolved while small-scale roughness is modelled with a wall model. Thus, the sensitivity of the power loss from resolved LEE to the modelled roughness level is investigated. Castorrini, Ortolani, and Campobasso (2023) find that the main cause of performance loss is the laminar to turbulent transition caused by the unresolved roughness. That said, extensive localised damages also yield performance losses regardless of the roughness level.

Castorrini, Alessio, Andrea Ortolani, and M. Sergio Campobasso. 2023. “Assessing the Progression of Wind Turbine Energy Yield Losses Due to Blade Erosion by Resolving Damage Geometries from Lab Tests and Field Observations.” Renewable Energy 218 (December): 119256. https://doi.org/10.1016/j.renene.2023.119256.