Numerical Analyses of Static and Dynamic Aeroelasticity Based on Unstructured CFD/CSD Solver

Comparing structured grid, unstructured grid has much more suitability for complex configurations, however, CFD-based on unstructured grid needs larger memory and computational time. In the paper, an implicit Euler solver based on unstructured tetrahedron grid and Lower-Upper Symmetric Gauss-Seidel scheme (LU-SGS) was first developed. An M6 standard wing model was used to validate the solver. Then the CFD solver coupled with CSD was developed to solve the fluid/structure interaction in aircraft engineering, in which an adaptive dynamic grid based on linear and torsion spring system was gotten with the conjugate gradient method, and the traditional Infinite Plate Spline (IPS) and a new three-dimensional radial basis function were applied the data transformation between fluid and structure. The time accuracy of fluid/structure solver can be achieved second order with the sub-iterations. Several investigations on static and dynamic aeroelastic problems are implemented in the paper. For a large aspect-ratio-wing, the static aeroelastic load distributions and its corresponding aerodynamic coefficients were mainly compared with that of rigid case. The dynamic aeroelasticity on a wing with winglet was investigated through the comparison of the flutter boundary with and without the winglet. Finally, the nonlinear limit cycle oscillations (LCOs) for complex wing/store configuration were simulated and analyzed.