Mamidala, RamuluAlajmi, Abdullah F.2021-10-292021-10-292021-10-292021Alajmi_washington_0250E_23438.pdfhttp://hdl.handle.net/1773/48066Thesis (Ph.D.)--University of Washington, 2021Harsh environments such as desert and arid environments are showing promising potential for energy production from wind turbine blades. However, when wind turbines are erected in such environments, unavoidable damage due to sand particle impingement during sandstorms, especially on the blade's leading edge, is expected. The leading edge erosion of wind turbine blades has a detrimental effect on the aerodynamic performance of the turbine. This investigation aims to experimentally study the erosion behavior of wind turbine blades when subjected to abrasive silica particles. The effect of multiple testing parameters on the intensity of erosion was investigated, such as the angle of impingement, erosion duration, and air pressure. The effect of protective coatings on reducing the intensity of erosion was also studied. Three types of coatings were used either as a single layer or in a multilayer coating system: graphene H-146, graphene IA-700, and polyurethane. It has been found that graphene has great potential as a protective coating against erosion since a single layer of H-146 provided up to 19% material removal reduction compared to an uncoated specimen. Moreover, combining a polyurethane layer on top of a graphene IA-700 layer showed a significant erosion reduction reaching up to 60% when protecting the leading edge of a wind turbine blade. The effect of these coatings on the aerodynamic performance of wind turbine blades was also studied. It has been found that the leading erosion causes an increase in drag coefficient, a decrease in lift coefficient, and a decrease in the amount of power generated. Protective coatings were able to reduce aerodynamic loss. In general, a combination of protective coatings made of graphene and polyurethane showed an excellent erosion resistance in terms of reduction in the amount of material removed, reduction in the depth of erosion scars, and reduction in the aerodynamic loss. In light of the results presented in this investigation, polyurethane/graphene IA-700 coating can be used as a protective measure for wind turbine blades in erosion-prone environments and should be further investigated in terms of actual field applications.application/pdfen-USCC BYAerodynamic performanceCoatingsGrapheneLeading edge erosionSolid Particle ErosionWind turbine bladesMechanical engineeringMechanical engineeringThesis