Control reversal and torsional divergence analysis for a high-aspect-ratio wing

Modern aircraft tends to adopt more flexible wing structures, such as high-aspect-ratio wings. They also feature advancements in performance, such as increased flight speeds. Thus, their aeroelastic characteristics and related safety factors became more important. By analyzing the static aeroelasticity of aircraft accurately, such as the control reversal and torsional divergence speed, it is expected that safe flights can be guaranteed within a prescribed flight envelope. In this paper, the control surface effectiveness and torsional divergence were analyzed using the following engineering tools: nonlinear multi-body dynamic analysis, DYMORE, cross-sectional analysis, two-cell analysis or VABS, and two-dimensional aerodynamic coefficient analysis for the subsonic isolated airfoil XFOIL. The results were verified through comparisons with those based on a typical section model with thin strip theory. Aluminum and composite single-cell box beam wings were analyzed in this paper. It is found that the control reversal and torsional divergence flight speeds as measured here were in good agreement with those predicted by a typical section model.