High-precision rotor blade aeroelastic analysis using three-dimensional nonlinear finite element formulation

Three-dimensional (3D) solid finite element analysis (FEA) is developed to perform a high-precision aeroelastic analysis of a rotor blade. This study is focus on geometrically nonlinearity and rotational effect. The 3D finite element (FE) formulation is based on updated Lagragian approach to estimate the large rotations and displacements. Moreover, the method to calculate the sectional loads of structure is presented based on force balance method. To do this, the internal force is adopted. For high-precision aeroelastic analysis, the 3D FEA is coupled with source-doublet panel method and vortex particle hybrid. The present analysis is verified using the rotating aluminum beam under centrifugal force for strains and stresses, and performs the sectional loads evaluation and aeroelastic analysis in hover using the multi-purpose unmanned helicopter (MPUH) blade developed by Korea Aerospace Research Institute. Accuracy of the present analysis is evaluated by comparing prediction of performance, structural behaviors, and sectional load results with those from CAMRAD II and experimental data.