基于等效梁模型的长直机翼动力学与颤振分析

针对多自由度的复杂结构,建立简化的等效结构模型,可以快速、有效地进行结构分析.采用能量等效的方法,将多自由度、结构复杂的长直结构等效为空间梁,推导得出等效梁的刚度值和惯量值,利用有限元法得到总体刚度阵和质量阵.针对某机翼模型,得出了等效梁的刚度值和惯量值,进行了振动和颤振特性分析,并分别与有限元软件的计算结果作了对比.结果表明:该等效建模法大大降低了结构自由度,振动及颤振分析误差较小,而且其主要参数值方便修改,因此该方法可用于飞行器的初级设计或结构优化设计.

Dynamic and flutter analysis of long-straight-wing based on equivalent beam model

For a complex structure of multiple degrees of freedom (DOF), building a simplified model of equivalent structure can lead to rapid and effective structural analysis. The method of energy equivalence was used to make a long-straight complex structure of multiple DOF equivalent to a beam element in space, the stiffness and inertia characteristics of the equivalent beam were derived, and the total stiffness matrix and mass matrix were obtained by using the finite element method. For a wing model, using the equivalence method, stiffness values and inertia values of the equivalent beam had been gotten. Analysis of vibration and flutter was carried out, and their respective results were separately compared with the calculation results of MSC Nastran. The contrast shows that the equivalent modeling method significantly reduces the structural DOF, and that the relative errors of results are small. And its main parameter values can be conveniently modified. Therefore, the method can be applied to preliminary design and structural optimization design of aircraft.