Design and finite element analysis of an ocean current turbine blade

A composite 3 meter ocean current turbine blade has been designed and analyzed using blade element theory (BET) and commercial finite element modeling (FEM) code, ANSYS. It has been observed that using the numerical BET tool created, power production up to 141 kW is possible from a 3 bladed rotor in an ocean current of 2.5 m/s with the proposed blade design. The blade is of sandwich construction with carbon fiber skin and high density foam core. It also contains two webs made of S2-glass for added shear rigidity. Four design cases were analyzed, involving differences in hydrodynamic shape, material properties, and internal structure. Results from the linear static structural analysis revealed that the best design provides adequate stiffness and strength to produce the proposed power without any structural failure. An eigenvalue buckling analysis confirmed that the blade would not fail from buckling prior to overstressed laminate failure if the loading was to exceed the safety factor.