A Staged Approach to Erosion Analysis of Wind Turbine Blade Coatings

Abstract
The current wind turbine leading-edge erosion research focuses on the end of the incubation period and breakthrough when analysing the erosion mechanism. This work presented here shows the benefits of splitting and describing leading-edge erosion progression into discrete stages. The five identified stages are: (1) an undamaged, as-new, sample; (2) between the undamaged sample and end of incubation; (3) the end of incubation period; (4) between the end of incubation and breakthrough, and (5) breakthrough. Mass loss, microscopy and X-ray computed tomography were investigated at each of the five stages. From this analysis, it was observed that notable changes were detected at Stages 2 and 4, which are not usually considered separately. The staged approach to rain erosion testing offers a more thorough understanding of how the coating system changes and ultimately fails due to rain droplet impacts. It is observed that during microscopy and X-ray computed tomography, changes unobservable to the naked eye can be tracked using the staged approach.