Zweiri, Feras (2024) Development of novel polyurethane coatings for protection of leading-edge of wind turbine blades. (PhD thesis), Kingston University, .
Abstract
Wind turbine performance is often hindered by leading-edge erosion (LEE), caused by factors such as rain, hail, UV radiation, sand, dust, insects, and other airborne particulates. LEE can degrade blade aerodynamics, reduce annual energy production (AEP), increase repair costs, and compromise structural integrity, ultimately leading to higher electricity costs. As a result, enhancing erosion protection, particularly for blade leading edges, is a very active area of research. Initially, computational fluid dynamics (CFD) analyses using ANSYS Fluent were carried out to evaluate the impact of erosion on lift, drag, and glide ratio. Damage to the leading edge was shown to reduce lift and increase drag, particularly at higher angles of attack. A 500k element 2D model using the 4-equation Transition Shear Stress Transport model (TSST) provided a good balance between computational efficiency and accuracy, while a five million element 3D model ensured grid independency. It was shown that the 2D model had 30 times lower computational cost than the 3D model, making it suitable for developing a digital twin to estimate turbine lifespan efficiently. The CFD results highlighted the need for effective leading-edge protection. Currently, polyurethane (PU) is widely used for this purpose. This project aimed to enhance PU coatings by incorporating nanomaterial additives, specifically graphene nanoplatelets (GNP), carbon nanotubes (CNT), and fumed nanosilica (SiO2). After extensive testing, the manufacturing process for the coatings was finalised, followed by physicochemical and mechanical characterizations, including differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), dynamic mechanical analysis (DMA), water contact angle (WCA), scanning electron microscopy (SEM), and energy-dispersive X-ray analysis (EDX). Mechanical tests assessed properties like Young’s modulus, tensile strength, elongation, tearing resistance, and wear resistance. Accelerated water uptake tests at 22°C, 32°C, and 45°C showed that pure PU had the highest permeability and lowest WCA, while PU+SiO2+GNP had the lowest permeability. Ultimately, the results from all the tests were compared, and the most efficient coating was identified. Among the options, PU+SiO2+CNT exhibited the best performance in terms of mechanical properties and water absorption.
Actions (Repository Editors)
 |
Item Control Page |