低速流场中柔性悬臂板的后颤振响应

Post flutter response of flexible cantilever plate in low speed flow field

建立了一个新的非线性气动弹性模型,对低速流场中柔性悬臂板的后颤振响应特性进行了分析。建模中考虑了结构几何非线性、气动力非线性以及两者之间的强耦合效应。通过实验数据对所建立的气动弹性模型进行了验证。发现在低速流场中柔性悬臂板可能会以周期加倍的方式进入混沌运动。结构几何非线性效应和翼尖涡引起的非定常气动力效应对柔性悬臂板的结构响应有显著影响,而尾涡变形引起的非定常气动力对结构运动的影响较小。还研究了不同耦合算法的差异,给出了小展弦比大柔性结构非线性气动弹性数值仿真时耦合策略的选择依据。

A new nonlinear aeroelastic model is established for the analysis of post flutter behavior of the flexible cantilever plate in low speed flows. Geometric nonlinearity, aerodynamic nonlinearity as well as the strong coupling effect between ge- ometric and aerodynamic nonlinearities are considered in the modeling. The aeroelastic model is verified with experimental data. The study shows that the flexible cantilever plate in low speed flows can enter into chaotic movement by means of periodic doubling in structural response. It is found that geometric nonlinearity and the unsteady aerodynamic effect caused by tip vortexes have significant impact on the structural response, while the unsteady aerodynamic force caused by deformation of wake vortexes has slight impact on the structural response. Different coupling strategies are also investigated to provide a reference for the selection of coupling strategy in nonlinear aeroelastic simulations of low-aspect-ratio flexible structures in low speed flows.