Aeroelastic Modeling of Full-Scale Airborne Wind Turbine Based on FSI Approach

The airborne wind turbine (AWT) employs a flying energy conversion to harvest the stronger winds blowing at higher altitudes. This study presents an aeroelastic evaluation of AWT which carries a flying rotor installed inside a buoyant shell. A considerable aerodynamic impact on the structural integrity of the full-scale system is modeled using fluid–structure interaction (FSI) approach. Both the fluid model and structure model are formulated separately and validated by a series of benchmark numerical data. To analyze the structural aeroelasticity, the aerodynamic loads from the fully-resolved computational model are coupled using one-way FSI to the structural model of the blade and shell to perform the non-linear static analysis. For detailed investigation, various wind loads from the bare and shell rotor configurations are imposed on the flexible structure. The generated torque, aerodynamic loads, tip deflection, stress estimation and operational stability of the proposed energy system are computed. The nonlinear aeroelastic characteristics in each case are found to be within the chosen design criteria according to material, operational speed and structural limits. Most importantly, the significant power gain justifies the structural response of the blade to withstand the shell induced loads at rated conditions in the shell configuration.