Aeroelastic Analysis of High-Aspect-Ratio Wings Using a Coupled CFD-CSD Method

In the present study, aeroelastic stability and the response of high-aspect ratio wings are numerically investigated using a coupled CFD-CSD method. The wing aerodynamic loads are calculated using a CFD flow solver based on unstructured meshes. The elastic deformation is evaluated using a FEM-based CSD solver employing a nonlinear flap-lag-torsion beam theory. The CSD solver also includes a built-in aerodynamics module based on a two-dimensional strip theory, coupled with a dynamic stall model, which is used for comparison with the coupled CFD-CSD method. Coupling of the CFD and CSD solvers is accomplished by adopting a conventional serial staggered method. At first, validation of the present coupled CFD-CSD method is made for an NACA0012 wing, and the predicted static deformation and dynamic response are compared with other predictions. The coupled method is then applied to an electric aerial vehicle wing, and the dynamic aeroelastic stability and response are investigated. It is found that the geometrical nonlinearity of the structure is responsible for degrading the dynamic stability of the wings. It is also found that the aeroelastic behaviors obtained using the coupled CFD-CSD method show higher aerodynamic damping than those of the strip theory-based analyses.