Elastic coupling is a feature specific to fiber-reinforced plastic materials, and it is often used in structures to improve stabilities or for other purposes. In the investigation of the elastic coupling properties, the commonly used finite element analysis (FEA) software package in structures does not usually provide a theoretical understanding. Thus, this study adopted a combined analytical and finite element beam model to address this problem. The model can provide better understanding on structures, and the computation time is far less than the FEA. This study examined several factors that may influence the couplings of wind turbine blades, such as material selection, coupling positions, and the wind force distribution. The results showed that mixed-use of carbon and glass fibers can provide better coupling properties, and the blade developers should arrange the off-axis fibers to adapt to the operating conditions in order to reach better performance.
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