Blade leading edge erosion damage due to droplet impact

Wind turbines play an increasingly vital role in the global renewable energy landscape, offering a sustainable alternative to fossil fuel-based power generation. Offshore wind energy holds great promise for producing substantial electrical output due to the larger swept area resulting from longer blades. Currently, the largest wind turbines have diameters of up to 236 m, with blade tip speeds surpassing 100 m/s. These high velocities cause interactions between blade tips and raindrops or other airborne particles, leading to gradual erosion, wear, and degradation over time. The leading edge of the wind turbine is the primary area impacted by raindrops, causing wear at both surface and sub-surface levels. Initially, damage is minimal, which is known as the incubation period. Following this phase, fatigue damage accelerates during the mass-loss-rate increasing period, necessitating the investigation of fatigue damage through the coating layers. To address this, a continuum fatigue damage model is proposed for lifetime prediction of coated substrates during the incubation period. This model offers several advantages, including the ability to accurately represent the progressive accumulation of damage over time and to capture complex interactions between material properties and loading conditions. By providing a continuous representation of fatigue damage, the model allows for better prediction of material behavior, especially during the early stages of degradation. Therefore, a finite element model was developed to analyze the coating fatigue lifetime under multi-point pressure impact with respect to three raindrop sizes with 50 m/s velocity during the incubation period. This model helps predict erosion rates and identify vulnerable regions on the blade surface that are most susceptible to accelerated wear.