Material selection in improving composite structured wind turbine blades

Different composite materials (carbon-vinylester, carbon-epoxy, carbon-phenolic, glass-vinylester, boron-epoxy) and different polymer foam core materials (PVC, PET, SAN, PU, PS, PEI) have been taken into consideration in the design of horizontal axis three-bladed wind turbine blades. Numerical data related to the density, young's modulus, poisson ratio and shear modulus, which reflect the mechanical properties of these materials, were obtained from the literature. The blade structure was modeled in accordance with the sandwich panel principleumerical data related to the density, young's modulus, poisson ratio and shear modulus, which reflect the mechanical properties of these materials, were obtained from the literature. The blade structure is modeled according to the sandwich panel principle. The blade consists of the upper and lower outer surface layers, the adhesive layer and the core layer located between the outer surface layers. As a result of using numerical data belonging to the considered composite and core materials through a computer-aided analysis program, Campbell diagram curves were created for each blade design. Modal analysis was performed for each material combination and the natural frequencies obtained from these analyses were compared with the rotor harmonic frequencies. Possible resonance risks were evaluated based on the behavior of flapwise, edgewise and torsional modes. Thus, the contributions of different material combinations to the structural vibration safety of the blade could be determined. In addition, the effect of material choices on the natural frequencies, mode shapes and resonance regions of the blades has been determined, and important results have been obtained in terms of structural safety and performance of wind turbine blades. The aim of the data obtained from the study is to guide and form the basis for material selection and future optimization studies in the manufacturing of wind turbine blades used in the industry.