Dynamic Characterization of Folded Wing Flutter Model Based on Substructure Mode Synthesis Method

Aiming to address the issue that folding wing research lacks robust modeling methods suitable for rapid analysis of structural dynamic characteristics and integrated research for experimental model verification, this paper deduces a rapid structural dynamic modeling method for folding wings based on the fixed interface substructure modal synthesis method. Following the principles of structural and functional similarity, a low-speed flutter experimental model of the folding wing with a continuous variable folding angle is designed and manufactured. For the folding wing model, the former main mode frequencies of the structure are obtained by the method of dynamic formula and ground percussion experiment, respectively. The experimental results show that the derived dynamic model is reliable. The P-k method and low-speed wind tunnel model experiment method are employed to study flutter characteristics of folding wing models. The results indicate that the critical flutter velocity is determined by the coupling of the first bending mode and the first torsional mode. The modal coupling trend is the same under different folding angles, but the critical flutter velocity is different. In addition, the damping coefficient has a significant effect on the critical flutter velocity, and the modal damping of the experimental model of the mechanically manufactured folding wing in this study ranges between 0.01 and 0.02.