Graphene Mediated Erosion Resistant Protection for Wind Turbine Blades

Abstract

The global transition to renewable energy has positioned wind power as a cornerstone of sustainable electricity generation. Yet, the efficiency and longevity of wind turbine blades are increasingly threatened by leading-edge erosion (LEE), a phenomenon driven by relentless high-velocity rain impacts. This degradation not only diminishes aerodynamic performance but can also reduce annual energy production (AEP) by up to 25%, escalating maintenance costs and undermining the economic feasibility of wind energy systems. To secure the future of wind power, innovative solutions are urgently needed to enhance blade durability and operational resilience in extreme environmental conditions. This study develops and optimises advanced graphene nanoplatelet (GNP)-reinforced epoxy/polysulphide nanocomposite coatings to enhance erosion resistance under real-world conditions. The coatings, based on EPON™ 828 epoxy resin modified with Thioplast™ EPS35 (EPS35) and GNP, were evaluated through mechanical, viscoelastic, and high-pressure erosion testing (100 bar and 150 bar). A key novelty lies in the combined use of accelerated weathering and erosion testing, providing a realistic assessment of coating performance over extended service life. The unmodified epoxy system exhibited poor flexibility, failing in mandrel tests; however, incorporating EPS35 improved performance. At 5% EPS35, crack length was reduced to ~48 mm, while 10% EPS35 enhanced crack resistance by 17.7% compared to 5%, exhibiting no cracks under impact loading. EPS35 also influenced viscoelastic properties, where 5% EPS35 reduced storage modulus (E’) by 23.4% and Tg by 7.6%, whereas 10% EPS35 increased E’ by 7.8% but decreased Tg by 9.3%. The optimal formulation, P-28 (0.025% GNP, 5% EPS35), demonstrated superior mechanical and thermal stability, exhibiting a 30.8% increase in E’, the highest Tg (68.3°C), and a 223.6% increase in crosslink density over the control. P-28 also outperformed commercial paint (CP) in erosion resistance, reducing material degradation by 38.9% and improving crack resistance by 90.84% at 100 bar. At 150 bar, P-28 maintained a 95.93% improvement in crack resistance. After 672 hours of weathering, P-28 exhibited 14.3% lower material degradation than CP, with crack resistance improved by 91.36%, reinforcing its durability under prolonged operational conditions. However, yellowing was observed post-weathering, suggesting possible photooxidative degradation, which may influence aesthetic properties but did not compromise mechanical integrity. These results highlight the potential of GNP-reinforced nanocomposites in mitigating LEE, extending blade lifespan, and reducing maintenance costs. The optimised coating offers a cost-effective, high-performance solution for improving wind turbine durability, supporting the continued growth of renewable energy technologies.

Date of Award	26 Jun 2025
Original language	English
Awarding Institution	Northumbria University
Supervisor	Ahmed Elmarakbi (Supervisor) & William Weaver (Supervisor)