共查询到19条相似文献,搜索用时 140 毫秒
1.
2.
3.
4.
压电材料因其变形精度高、反应速度快、易于制作成小型化元件已经被广泛应用于精密驱动、振动控制、精确定位等领域。改变压电智能结构中压电元器件的位置、大小、形状等参数能够有效地改善系统的力学性能,因而吸引了许多学者和工程师的关注和研究。拓扑优化作为有效的优化工具,已经成功应用于压电智能结构的优化设计中。本文首先阐述了压电智能结构拓扑优化的背景和意义,简要回顾了压电智能结构主动控制及分析方法,并综述了面向结构静变形控制的压电智能结构优化、面向振动控制的压电智能结构优化、压电俘能器的设计与优化等三个方面的研究进展。最后,简单归纳压电智能结构拓扑优化研究中值得关注的几个问题。 相似文献
5.
6.
7.
币压电传感器、作动器和梁组成的机电耦合的动力系统,本文提出了一个计算机数值模拟的伽辽金方法。从哈密顿原理出发,导出其状态方程,采用有限维样条函数逼近该动力系统的运动。算便与实验结果比较表明,本文提出的方法,对于机电耦合梁的振动控制分析是有效的。此方法也容易进一步推广到其他更为复杂的智能结构。 相似文献
8.
压电智能结构拓扑优化研究进展 总被引:1,自引:0,他引:1
压电材料因其变形精度高、反应速度快、易于制作成小型化元件已经被广泛应用于精密驱动、振动控制、精确定位等领域。改变压电智能结构中压电元器件的位置、大小、形状等参数能够有效地改善系统的力学性能,因而吸引了许多学者和工程师的关注和研究。拓扑优化作为有效的优化工具,已经成功应用于压电智能结构的优化设计中。本文首先阐述了压电智能结构拓扑优化的背景和意义,简要回顾了压电智能结构主动控制及分析方法,并综述了面向结构静变形控制的压电智能结构优化、面向振动控制的压电智能结构优化、压电俘能器的设计与优化等三个方面的研究进展。最后,简单归纳压电智能结构拓扑优化研究中值得关注的几个问题。 相似文献
9.
10.
11.
12.
Based on the Talreja’s damage model with tensor valued internal state variables, considering the effects of piezoelectricity, geometrical nonlinearity and the constitutive relations of the composite uni-ply plate with matrix cracks, the nonlinear dynamic equations of piezoelectric laminated plates with damage are established and the problems are solved by using the finite difference method. In numerical calculating examples, the nonlinear dynamics responses and the fatigue damage evolution curves of the plates are obtained, and the effects of piezoelectric materials, damage and external load on the nonlinear dynamic response and fatigue damage evolution of the plates are discussed. 相似文献
13.
Considering mass and stiffness of piezoelectric layers and damage effects of composite layers, nonlinear dynamic equations of damaged piezoelectric smart laminated plates are derived. The derivation is based on the Hamilton's principle, the higher- order shear deformation plate theory, von Karman type geometrically nonlinear straindisplacement relations, and the strain energy equivalence theory. A negative velocity feedback control algorithm coupling the direct and converse piezoelectric effects is used to realize the active control and damage detection with a closed control loop. Simply supported rectangular laminated plates with immovable edges are used in numerical computation. Influence of the piezoelectric layers' location on the vibration control is in- vestigated. In addition, effects of the degree and location of damage on the sensor output voltage are discussed. A method for damage detection is introduced. 相似文献
14.
Research and development of active monitoring systems for reinforced concrete structures should lead to improved structural safety and reliability. Numerical models of active monitoring and damage detection systems can help in the development and implementation of these systems. Modeling of damage detection process in a concrete beam with piezoelectric sensors/actuators based on wave propagation is investigated in this paper. Numerical modeling process is divided into two parts: (1) piezoelectric smart aggregates (SA), and (2) wave propagation models. Displacement obtained in the SA model is used as an input parameter for the modeling of wave propagation. Wavelet analysis is used as a signal processing tool and the damage index is calculated based on the wave energy. In this paper root-mean-square deviation (RMSD) damage index is used. Damage indices obtained by this numerical analysis are compared with experimental results. Very good fit between the finite element (FE) results and experimental results confirm a good FE approach of this problem. 相似文献
15.
将模糊逻辑与学习控制的基本思想相结合,根据控制系统的动态输出特性,采用模糊控制对学习控制律中的参数进行实时校正,实现系统的动态学习过程,提出了一种适用于压电智能结构振动控制的模糊自学控制方法FSLC(FuzzySelf-LearningContr01)。分别采用三维8节点实体单元(Solid45)和耦合单元模拟主结构和压电致动器/传感器,基于ANSYS参数化语言编写了压电智能结构振动控制分析的有限元程序。通过数值仿真证明了模糊自学习控制方法能有效控制压电结构的振动,并提高了自学习控制的收敛速度和获得了很好的控制效果。 相似文献
16.
In order to improve the joint failure strength, an adhesively bonded smart composite pipe joint system has been developed by integrating electromechanical coupling piezoelectric layers with the connection coupler. It has been validated that the integrated piezoelectric ceramic layers can smartly reduce stress concentration in the adhesive layer bond-line under bending or axial tension loads. In this study, piezoelectric particle/fiber reinforced polymer composite was utilized to construct adhesively bonded smart composite pipe joint systems, in order to overcome the brittle characteristic of the piezoelectric ceramic layers and to facilitate joint construction. Since torsion is one of the dominating loading conditions in practice, the behavior of the newly developed smart pipe joint system subjected to torsion loading was investigated in-detail to evaluate the effect of the integrated piezoelectric reinforced polymer composite layer on the joint performance. Firstly, based on the first-order shear deformation theory, the fundamental equations with relevant boundary and continuity conditions were developed to theoretically model the smart pipe joint system subjected to torsion loading. Further, the analytical solutions for the mid-plane displacements and the shear and peel stresses in the adhesive layer were obtained by using the Levy solution and the state-space method. Finally, some numerical examples were presented to evaluate the detailed effect of the stacking sequence and thickness of the integrated composite piezoelectric layers in the connection coupler on reducing the stress concentration in the adhesive layer; the effect of the applied electric fields on shear and peel stresses in the adhesive layer was also illustrated. 相似文献
17.
弹性模量是工程材料重要的性能参数, 可以衡量物体抵抗弹性变形的能力. 弹性成像是一种通过弹性模量表征生物体组织物理特性的医学成像方法. 为了将弹性成像应用于机械装备结构的缺陷识别, 提高弹性成像的局部表征和全局识别能力, 提出一种基于拓扑优化的结构弹性成像方法. 受拓扑优化理论启发, 采用结构离散单元的相对密度(弹性模量系数)作为弹性成像参数来表征损伤程度, 建立成像参数与弹性模量的插值模型, 基于有限元模型构建损伤表征、结构模型与物理响应的映射关系. 以损伤结构和无损结构位移响应的最小二乘为目标函数, 以成像参数上下限为约束, 建立结构弹性成像的优化模型. 以伴随法推导弹性成像问题的灵敏度, 并详细给出了弹性成像反演的数值实施方式. 二维悬臂梁和米歇尔梁算例表明, 本文提出的基于拓扑优化的弹性成像方法无需先验损伤信息, 可有效实现均质/非均质、单/多缺陷结构的弹性成像, 且弹性成像结果不依赖于特定的边界条件, 进一步将弹性成像方法扩展至三维悬臂梁问题验证了其通用性. 相似文献
18.
《International Journal of Solids and Structures》2006,43(5):1291-1307
Surface-bonded piezoelectric actuators can be used to generate elastic waves for monitoring damages of composite materials. This paper provides an analytical and numerical study to simulate wave propagation in an anisotropic medium induced by surface-bonded piezocermic actuators under high-frequency electric loads. Based on a one-dimensional actuator model, the dynamic load transfer between a piezoceramic actuator and an anisotropic elastic medium under in-plane mechanical and electrical loading is obtained. The wave propagation induced by the surface-bonded actuator is also studied in detail by using Fourier transform technique and solving the resulting integral equations in terms of the interfacial shear stress. Typical examples are provided to show effects of the geometry, the material combination, the loading frequency and the material anisotropy of the composite upon the load transfer and the resulting wave propagation. 相似文献
19.
This paper presents a nonlinear model for cross-ply piezoelastic laminated plates containing the damage effect of the intralayer
materials and interlaminar interfaces. The model is based on the general six-degrees-of-freedom plate theory, the discontinuity
of displacement, and electric potential on the interfaces are depicted by three shape functions, which are formulated according
to solutions about three equilibrium equations and conservation of charge. By using the Hamilton variation principle, the
three-dimensional nonlinear dynamic equations of piezoelastic laminated plates with damage are presented. Then using the finite
difference method and the Newmark scheme, an analytical solution is presented. In numerical examples, the effects of different
damage models, damage evolution, amplitude and frequency of electric loads on the nonlinear dynamic response of piezoelectric
laminated plate with interfacial imperfections are investigated. 相似文献