Improving Aeroelastic Stability of a Vertical Axis Wind Turbine SimplifiedRectangular Composite Blade

In this research, the aeroelastic stability of a blade made of composite material has been investigated and theeffects of lay-up, aspect ratio, and blade thickness on flutter and divergence speeds and flutter frequency have beenstudied. The model considered for simulating the blade is a laminated rectangular cantilever plate with threedimensionalfluid flow on top of it. One of the best theories so far presented for computing the unsteady aerodynamicforces on the vibrating plate is the Doublet-Lattice Method (DLM), which has been used in this research. The structuraland modal analyses have been performed using Finite Element Method (FEM) and coding in the MATLABenvironment. The surface spline was used to couple the aerodynamic and structural loads. Finally, the P-K method wasused to determine the flutter speed. It can be observed from the studies carried out in this research that the aeroelasticcharacteristics of a composite blade in addition to its structural characteristics such as natural frequencies areconsiderably affected by thickness, aspect ratio, and lay-up. The results show that the blade with a lay-up angle of ۴۵degrees exhibits the best resistance to flutter and divergence. Furthermore, the aeroelastic instability speed increaseswith an increase in blade thickness but decreases with an increase in aspect ratio.