基于流形切空间插值的折叠翼参数化气动弹性建模

变体飞行器的气动弹性力学建模是当前先进飞行器设计的研究热点和难点. 然而传统的气动弹性动力学建模方法对于具有结构参变特性的变体飞行器气动弹性力学研究存在建模效率低、计算复杂等问题. 本研究提出了一种基于流形切空间插值的可折叠式变体机翼参数化气动弹性建模方法. 首先, 该方法建立若干个典型折叠角下的折叠翼结构有限元模型, 通过流形切空间插值方法建立折叠翼参数化结构动力学模型. 其次, 采用偶极子网格法得到参数化非定常气动力模型, 进而建立气动和结构相互耦合的折叠翼参数化气动弹性模型. 为了验证该参数化建模方法在折叠翼气动弹性分析中的准确性, 本文以一小展弦比折叠翼为研究对象, 从折叠翼自由振动时的参变模态特性、颤振边界预测两方面进行了算例验证, 并与直接计算方法进行了对比, 进一步验证了参数化气动弹性模型的有效性. 研究结果表明, 该参数化气动弹性模型对上述两类问题的计算精度与直接计算方法一致, 并且有着计算效率更高的优势. 

PARAMETRIC AEROELASTIC MODELING OF FOLDING WING BASED ON MANIFOLD TANGENT SPACE INTERPOLATION

The parametric aeroelastic modeling of a morphing aircraft is a hot topic in the research field of morphing aircraft design. However, the traditional non-parametric aeroelastic dynamic modeling methods have some problems, such as low modeling efficiency and complex aeroelastic analysis for for aeroelastic research of morphing aircraft with structural parametric characteristics. In this paper, a parametric aeroelastic modeling method of folding wing based on the tangent space interpolation is proposed. Firstly, based on the structural finite element models of a folding wing at several folding angles, a parametric structural dynamic model of the folding wing is established by tangent space interpolation. Then, the parametric unsteady aerodynamics is computed by the Doublet Lattice method. At last, the parametric aeroelastic model of the folding wing is obtained by coupling the structural dynamics and unsteady aerodynamics. To verify the accuracy of the parameterized model in the aeroelastic calculation, a small aspect ratio folding wing is taken as the research object. The dynamic characteristics including the natural frequencies, mode shapes, and flutter boundaries at different folding angles are efficiently calculated. In addition, the numerical results computed via the present parametric method are compared with the direct non-parametric method. The demonstration shows that the results from the parametric aeroelastic model is consistent with the direct method for the aeroelastic problems and has the advantage of higher calculation efficiency.