Abstract:
This dissertation investigates the feasibility and aero-structural performance of a novel biplane wind turbine blade design as a solution to the structural challenges of creating very large (100-meter class) blades. The core of the study is a "structures-first" aero-structural analysis framework that integrates Blade Element Momentum (BEM) theory for aerodynamic load prediction with detailed structural analysis using the Finite Element method. A comprehensive Finite Element model of the biplane blade was developed using shell elements for the blade sections and beam elements for the spar caps, with composite material properties generated by the PreComp tool. The FEA model was used within an optimization loop to minimize blade mass while satisfying critical structural constraints, including material stress limits, buckling, and tip deflection, under extreme and fatigue load cases. The results from the Finite Element analysis demonstrate that the biplane blade concept is structurally feasible and can offer significant mass savings and reductions in the cost of energy compared to a conventional monoplane reference blade by efficiently carrying bending loads in its inboard region.
