Effects of damage parametric changes on the aeroelastic behaviors of a damaged panel

摘要

In this study, the aeroelastic responses and stability boundaries of a simply supported supersonic plate with structural damage are investigated to assess the effects of damage parametric changes on the stability regions as well as to explore some potential tools for damage detection. In the modeling, structural damage is a local bending stiffness loss with various levels, extents and positions. The effects of damage level, extent and position are presented via exploiting nonlinear tools such as bifurcation diagrams, stability regions, Poincare maps and Lyapunov exponents. Specially, the proper orthogonal decomposition (POD) method is applied to extract the POD modes to detect the damage parametric variations. It is determined that (1) structural damage has a notable influence on the aeroelastic stability of the panel; (2) the damage level and extent affect in a similar way that a larger damage level/extent tends to reduce the flutter boundary for a flat plate, but conversely increase the flutter boundary for a buckled plate; (3) the damage occurring around the leading of the panel corresponds to the least stable panel compared to the other positions along the chordwise; (4) the stability region as a novel way for damage detection is proved to be sensitive and effective, and the largest Lyapunov exponent as a quantitative measure is powerful to reveal the subtle differences in the chaos induced by damage changes; (5) the higher-order POD modes are more sensitive to the subtle damage than the primary POD modes.