压电曲壳单元及其形状控制

SHAPE CONTROL OF PIEZOELECTRIC SHELL STRUCTURES

板壳结构作为航空、航天工程中的主要工作元件,要承受多种环境荷载,而对形状变化非常敏感的机翼、天线等结构,有必要进行形状控制。推导了空间压电曲壳单元的有限元方程,采用约束方程法连接压电曲壳和主体结构,建立了整体结构的有限元分析模型,并基于等效应变原则验证了模型的正确性。在此基础上,利用最小二乘法对结构进行了形状控制,得到压电驱动器上电压的最优分布。算例表明:该文模型能提高计算精度和速度,达到形状控制的要求。

As major structures used in space engineering, plates and shells often endure varied loads. Working performance of some structures, such as airfoil and antenna, are very sensitive to their shapes and deformations. Thus, it is necessary to control the structure shape by some technologies. This paper presents a finite element formulation for the numerical simulation of the spatial curved shell structures with piezoelectric actuators, in which the host shells and piezoelectric patches are combined with constraint equatioias directly. The use of the constraint equations reduces the number of the DOF and improves the computation efficiency. Based on the proposed model, the optimum structural shape and a perfect voltage distribution can be obtained by using the linear least square method. Numerical examples are given to demonstrate the validity of the proposed model.