High-fidelity Blade Aeroelastic Modeling and Load Analysis using Three-dimensional Finite Element-based Multibody Solver for Lift-offset Coaxial Rotor

This study presents a high-fidelity aeroelastic analysis for lift-offset coaxial rotors based on a three-dimensional (3D) finite element (FE) multibody dynamic analysis. The structural model is based on an updated Lagrangian formulation to capture geometrically nonlinear behavior. The internal aerodynamic model uses lifting line theory with linear inflow model, while the external aerodynamic model employs a panel/vortex particle method to predict aerodynamic loads. The lift-offset coaxial rotor developed by Korea Aerospace Research Institute is employed to investigate the aeroelastic response and the coupling analysis is performed on hover flight condition. The results obtained from the aeromechanics analysis using uniform inflow are compared with CAMRAD II in terms of blade displacement and sectional loads. Furthermore, through high-fidelity aeroelastic analysis using panel/vortex particle method, rotor–rotor aerodynamic interactions and structural loads, and 3D stress and strain distributions are investigated.