Calculation of transonic unsteady aerodynamic force for high-aspect ratio flexible wing using improved unstructured dynamic grids method

Spring analogy method for unstructured dynamic grids is studied. The spring stiffness in the vertex spring method is analyzed. Improvements considering squashing spring effect and boundary effect are developed to the standard method. Applications of the improved spring analogy method to dynamic grids generation show that the new method greatly improves the deforming ability and the quality of the grids. This improved unstructured dynamic mesh method, coupled with ALE Euler solver, is then applied to simulate transonic unsteady flow about bend-torsion oscillation of high-aspect ratio flexible wing of High-Altitude-Long-Endurance Unmanned Aerial Vehicles. The computation results show the developed method in this paper is feasible to calculate transonic unsteady aerodynamic force of high-aspect ratio flexible wing.