一种基于结构动力学的柔性扑翼气动结构耦合方法研究  

Research on Aerodynamic-structural Coupling of Flexible Flapping Wings

作　　者：陈利丽[1,2] 宋笔锋[1] 宋文萍[1] 杨文青[1] 

机构地区：[1]西北工业大学翼型叶栅空气动力学国家重点实验室,陕西西安710072 [2]中航工业第一飞机设计研究院,陕西西安710089

出　　处：《航空学报》2013年第12期2668-2681,共14页Acta Aeronautica et Astronautica Sinica

基　　金：国家自然科学基金(20100481369)~~

摘　　要：基于结构动力学理论,发展了一套适用于扑翼气动结构耦合特性的数值模拟方法:采用计算流体力学(CFD)方法数值模拟扑翼的非定常绕流,得到扑翼的非定常气动特性,基于计算结构力学(CSD)方法求解扑翼结构动力学方程得到扑翼的动态结构变形位移,从而得到周期内各时刻的扑翼外形,重复上述过程直至气动、结构变形均收敛。其中,扑翼非定常气动特性通过求解雷诺平均Navier-Stokes方程得到。对于结构动态特性,首先基于Hamilton原理推导了扑翼的结构运动方程,并对动能和应变能进行变分,得到扑翼动力学方程,然后利用结构有限元方法对该方程进行离散并求解。通过与实验结果进行对比,验证了本文所发展求解程序的有效性。在此基础上针对实际柔性扑翼的简化模型展开数值模拟,研究了柔性变形对扑翼气动特性的影响,并进一步对刚性和柔性扑翼流场细节进行比较,分析研究了结构变形对柔性扑翼气动特性的影响机理。Due to the coupling between large prescribed motions and flexible deformation, classical dynamics theory cannot be applied to a flapping wing＇s aeroelastic studies. In this paper, a dynamic aerodynamic-structural coupling computational framework is developed which is able to simulate the aerodynamic-structural coupling characteristics of a flapping wing. First of all, the periodic aerodynamic load of the flapping wing is obtained by a computational fluid dynamics （CFD） solver; then a computational structure dynamics （CSD） solver is used to get the periodic structural deformation as well as the periodic shape of the flapping wing. Repeat the procedure until structural deformation is converged. The flapping wing＇s unsteady aerodynamic characteristics are obtained by solving the Reynolds average Navier-Stokes equations. Structural dynamic equations capable of describing the flapping wing＇s movement are derived by use of the Hamilton principle, and then they are discretized through the finite element method. The discrete forms of the dynamic structural equations are then reduced to a series of easy-to-solve second order differential equations through modal analysis. Computational results show good agree- ment with experimental results, which proves that the proposed method is valid and suitable for simulation of a flexible flap- ping wing. Both rigid and flexible wing results of flow field details are further presented to demonstrate the effects of wing flexibility on aerodynamic performance.

关 键 词：扑翼 气动结构耦合 非定常流动 空气动力学 结构动力学 柔性结构 

分 类 号：V211.3[航空宇航科学与技术—航空宇航推进理论与工程]