【作者】 张宏亮；

【导师】 韩景龙；

【作者基本信息】 南京航空航天大学 ， 一般力学与力学基础， 2008， 硕士

【摘要】 压电智能结构的气动弹性主动控制是当前国际上气动弹性领域内的研究热点之一。本文以压电智能复合材料盒型机翼为研究对象,对气动弹性主动控制系统的结构特性以及开闭环颤振特性进行了较为深入地分析。对压电智能复合材料盒型机翼结构,按照经典层合板理论,采用20个位移自由度和8个电自由度的四边形板单元,利用Hamilton变分原理,详细推导了压电智能复合材料盒型机翼的有限元运动方程,并通过算例验证本文有限元程序是可行的。利用偶极格子网法计算空气动力影响系数矩阵,利用子空间法将空气动力影响系数矩阵拟合成时域有理函数形式,建立了压电智能复合材料盒型机翼的状态空间颤振方程。依次利用模态截断法、最小实现、平衡降阶法对系统方程进行了降阶处理。以提高颤振速度为目标,利用H∞控制理论对于降阶后的系统方程求解出能抑制外界干扰力的动态输出反馈控制器,并与降阶后的状态空间方程相结合,形成闭环控制系统。最后,对建立单输入单输出系统和多输入多输出系统模型等多种情况进行了理论分析。讨论了压电片的放置位置对颤振速度的影响。计算结果表明,通过主动控制律的实施,达到了颤振主动抑制的目的。更多还原

【Abstract】 Active aeroelastic control of piezoelectric smart structure is one of the hotspot in the field of aeroelasticity. The main task of this paper is to study the flutter characteristics of piezoelectric smart box wing. The flutter characteristics of open-loop and close-loop as well as structure characteristics of active aeroelastic control system are deeply analyzed.Based on the classical laminate theory, the quadrilateral plate element which contains 20 displacement DOF and 8 electrical DOF is used to study the structure of piezoelectric smart composite box wing. This paper also deduces the finite element equations of piezoelectric smart box wing via Hamilton principle and an example is presented to demonstrate the validity of the finite element program.The aerodynamic influence coefficient (AIC) matrice is calculated by using the Doublet Lattice Method and approximated as a rational function in time domain by using the new state-space method. The state space equations of the aeroservoelastic system are formulated and the reduction of system equations uses the following process in turn: Model truncation, Minimal realization and Balancing reduction.To increase the flutter speed, H∞-control theory is used to design dynamic output feedback controller which can suppress the disturbance for the reduced system, and the close-loop system is formed by integrating the controller with the reduced system.At last, a single input/single ouput model and a multi input/multi output model of close-loop system are analyzed respectively. The influences of the location of piezoelectric material on the flutter speed are simply discussed. The results indicate that the flutter can be suppressed through active aeroelastic control law design.更多还原