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5介绍了一种新型的压电作动器—层叠式压电作动器,并使用这种作动器对温度场中的梁进行了形状控制研究。根据哈密顿原理,得到了粘贴有层叠式压电作动器的梁结构的控制方程,进行了数值仿真,并且用Comsol软件进行了模拟,两者的结果基本一致。对压电作动器的控制电压进行了优化,得到了最优控制电压。由于层叠式压电作动器的控制力与压电片的层数成二次函数关系,当控制电压恒定时,层叠式压电作动器的控制力随着压电器层数的增加而迅速减小。使用层叠式压电作动器可以在比其他作动器更小的电压下取得更好的控制效果。通过与普通压电作动器的比较,可以发现层叠式压电作动器可以有效地降低作动器的施加电压,而且可以显著增强控制效果。这种形状控制方法为应用层叠式压电作动器进行薄壁结构的形状控制提供了理论基础。 相似文献
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用压电元件实现复合材料层合板振动控制的数值分析 总被引:9,自引:0,他引:9
采用板的一阶剪切变形理论,对含有压电材料层的复合材料层合板,从机电耦合的变分方程及Hamilton原理出发,建立起求解其动态响应 的有限元方程。同时也给出了压电材料层作为传感元件时的传感方程及作为作动元件时的作动方程。并采用速度反馈控制实现了层合板的主动振动。最后给出了计算实例。 相似文献
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考虑作动器联接方式的结构形状控制优化 总被引:1,自引:0,他引:1
以压电材料梁式作动器控制复合材料层合板形状的设计问题为对象,研究有限个独立控制参数条件下的形状最优控制问题。研究了作动器与信号发生器(独立控制参数)联接关系的参数化描述方式,建立了作动器联接方式与控制参数协同设计的问题提法;针对优化问题中离散变量(联接方式描述参数)和连续变量(控制参数)共存的特点,建立了遗传算法和线性最小二乘(Linear Least Square,LLS)方法相结合的求解策略和方法;在响应分析所采用的有限元模型中,采用粘结层单元描述本体结构与作动器之间的连接。复合材料层合板形状控制设计的实例,验证了该文中建立的问题提法、优化模型和求解策略的有效性。 相似文献
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研究了压电结构中压电片厚度和嵌入深度的优化问题。首先给出了压电层合板的高阶耦合分析模型;然后以不受约束的含压电铺层复合材料板为代表,在压电层厚度方向施加电场时板自由变形,假设板任意微元横截面上内力为零,以其弯(扭)曲曲率最大为优化目标,建立了求解压电片最优厚度和嵌入深度问题的约束优化模型。最后分别以各向同性板中嵌入各项同性压电片和复合材料板中嵌入各向异性压电片为例进行了分析,绘出了目标函数的三维曲面图及等高线图,结果表明压电片的作动效能与其厚度和嵌入位置密切相关,而最优厚度和嵌入位置是由压电片和基体的材料特性决定的。 相似文献
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压电层合板可以通过对作动器施加电压变形为各种形态,在智能可折叠结构领域具有潜在的应用前景。理解这种结构的大变形作动机理是软体智能结构设计的基础。利用等效单层模型,基于绝对节点坐标法(ANCF),建立了一种柔性压电层合薄板单元。引入了压电材料的本构方程来推导弹性力和压电力,建立了压电层合薄板单元的动力学方程,并对比了在大变形范围内三种曲率表达形式的收敛效果。通过与ABAQUS有限元软件求得的结果进行比较,验证了压电层合薄板单元的正确性,并给出了一些大变形算例。结果表明,在压电材料全覆盖、部分覆盖、多段覆盖等情形下,该单元均能得到较为稳定的结果,表明此单元可以与单层线弹性单元进行耦合。此外还研究了压电层合板受集中力状态下的动态响应。该研究有助于理解受智能压电材料驱动的柔性或软体结构的复杂耦合非线性力学行为。 相似文献
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压电复合(层合)结构可应用于结构振动控制、形状保持、健康监测等,建立压电层合结构精确的机电耦合计算模型成为了研究的焦点.针对表面粘贴或内部嵌入压电片的压电层合板结构,基于高阶位移场和高阶电势模型,根据Hamilton原理建立了机电耦合高阶有限元模型.该模型适用于薄板和中厚板,并且能够捕捉压电层内沿厚度方向呈抛物线型分布的诱导电势.以压电双晶片简支板为例,进行了作动器构型和开环、闭环状态传感器构型的数值分析.结果指出,诱导电势对压电传感器有重要影响,而压电作动器可忽略这种电势. 相似文献
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Mehdi Bohlooly 《Advanced Composite Materials》2017,26(5):407-426
A thermomechanical buckling analysis is presented for simply supported rectangular symmetric cross-ply laminated composite plates that are integrated with surface-mounted piezoelectric actuators and are subjected to the combined action of in-plane compressive edge loads, two types of thermal loads, and constant applied actuator voltage. The formulation of equations is based on the classical laminated plate theory and the von-Karman non-linear kinematic relations. The analysis uses an exact method to obtain closed-form solutions for the buckling load. The effects of applied actuator voltage, thermal and mechanical loads, plate geometry, and lay-up configuration of the laminated plates are investigated. The novelty of the present work is to obtain closed-form solutions for electro-thermomechanical buckling of hybrid composite plates, and to cover non-uniform temperature distribution loading. The results for various states are verified with known data in the literature. 相似文献
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Hui-Shen Shen 《Composite Structures》2009,91(3):375-384
Compressive postbuckling under thermal environments and thermal postbuckling due to a uniform temperature rise are presented for a simply supported, shear deformable functionally graded plate with piezoelectric fiber reinforced composite (PFRC) actuators. The material properties of functionally graded materials (FGMs) are assumed to be graded in the thickness direction according to a simple power law distribution in terms of the volume fractions of the constituents, and the material properties of both FGM and PFRC layers are assumed to be temperature-dependent. The governing equations are based on a higher order shear deformation plate theory that includes thermo-piezoelectric effects. The initial geometric imperfection of the plate is taken into account. A two step perturbation technique is employed to determine buckling loads (temperature) and postbuckling equilibrium paths. The numerical illustrations concern the compressive and thermal postbuckling behaviors of perfect and imperfect, geometrically mid-plane symmetric FGM plates with fully covered or embedded PFRC actuators under different sets of thermal and electric loading conditions. The results for monolithic piezoelectric actuator, which is a special case in the present study, are compared with those of PFRC actuators. The results reveal that, in the compressive buckling case, the applied voltage usually has a small effect on the postbuckling load–deflection curves of the plate with PFRC actuators, whereas in the thermal buckling case, the effect of applied voltage is more pronounced for the plate with PFRC actuators, compared to the results of the same plate with monolithic piezoelectric actuators. 相似文献
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Sung Yi Shih Fu Ling Ming Ying Harry H. Hilton Jack R. Vinson 《International journal for numerical methods in engineering》1999,45(11):1531-1546
A finite element algorithm has been developed for the efficient analysis of smart composite structures with piezoelectric polymer sensors or/and actuators based on piezoelectro‐hygro‐thermo‐viscoelasticity. Variational principles for anisotropic coupled piezoelectro‐hygro‐thermo‐viscoelasto‐dynamic problems have also been proposed in this study. As illustrative studies, dynamic responses in laminated composite beams and plates with PVDF sensors and actuators are obtained as functions of time using the present finite element procedures. The voltage feedback control scheme is utilized. The proposed numerical method can be used for analysing problems in the design of smart structures as well as smart sensors and actuators. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
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Quasi-static shape control of a smart structure may be achieved through optimizing the applied electric fields, loci, shapes and sizes of piezoelectric actuators attached to the structure. In this paper, a finite element analysis (FEA) software has been developed for analyzing static deformation of smart composite plate structures with non-rectangular shaped PZT patches as actuators. The mechanical deformation of the smart composite plate is modeled using a 3rd order plate theory, while the electric field is simulated based on a layer-wise theory. The finite element formulation is verified by comparing with experimentally measured deformation. Numerical results are obtained for the optimum values of the electric field in the PZT actuators to achieve the desired shape using the linear least square (LLS) method. The numerical results demonstrate the influence of the shapes of actuators. 相似文献
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A simulation study on the thermal buckling behavior of laminated composite shells with embedded shape memory alloy (SMA) wires 总被引:1,自引:0,他引:1
In this paper, numerical simulation analyses of the thermal buckling behavior of laminated composite shells with embedded shape memory alloy (SMA) wires were performed to investigate the effect of embedded SMA wires on the characteristics of thermal buckling. In order to simulate the thermomechanical behavior of SMA wires, the constitutive equation of the SMA wires was formulated in the form of an ABAQUS user subroutine. The computational program was verified by showing the response of the pseudoelasticity and shape memory effect (SME) at various temperatures and stress levels. Modeling of the laminated composite shells with embedded SMA wires and thermal buckling analyses were performed with the use of the ABAQUS code linked with the subroutine of the formulated SMA constitutive equations. The thermal buckling analyses of the composite shells with embedded SMA wires show that the critical buckling temperature can be increased and the thermal buckling deformation can be decreased by using the activation force of embedded SMA wire actuators. 相似文献
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《Composite Structures》2007,77(2):249-262
A two-dimensional global higher-order deformation theory is presented for the free vibration and stability problems of angle-ply laminated composite and sandwich plates subjected to thermal loading. By using the method of power series expansion of continuous displacement components, a set of fundamental governing equations which can take into account the effects of both transverse shear and normal stresses is derived through Hamilton’s principle. Several sets of truncated Mth order approximate theories are applied to solve the eigenvalue problems of a simply supported angle-ply multilayered plate. Natural frequencies and critical temperatures of angle-ply laminated composite and sandwich plates subjected to thermal loading are obtained. Critical temperatures are obtained by increasing the temperature until the natural frequency vanishes. The effects of prebuckling displacements on the natural frequencies and critical temperatures are taken into account. Modal displacement distributions through the transverse direction of the laminates are plotted for the specific temperature parameter. Numerical results are compared with those of the published existing theories. The present global higher-order approximate theories can predict the natural frequencies and critical temperatures of angle-ply laminated composite and sandwich plates subjected to thermal loading accurately within small number of unknowns. 相似文献
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Aurelio L. Araújo Cristovao M. Mota Soares Carlos A. Mota Soares 《Applied Composite Materials》2010,17(5):529-542
In this paper we present a finite element model for the analysis of active sandwich laminated plates with a viscoelastic core
and laminated anisotropic face layers, as well as piezoelectric sensor and actuator layers. The model is formulated using
a mixed layerwise approach, by considering a higher order shear deformation theory (HSDT) to represent the displacement field
of the viscoelastic core and a first order shear deformation theory (FSDT) for the displacement field of the adjacent laminated
anisotropic face layers and exterior piezoelectric layers. The dynamic problem is solved in the frequency domain with viscoelastic
frequency dependent material properties for the core. Control laws are also implemented for the piezoelectric sensors and
actuators. The model behaviour in dynamics is assessed with the few solutions found in the literature, including experimental
data, and a laminated composite active sandwich application is proposed. In this numerical application, velocity feedback
control law is implemented for active control, using co-located piezoelectric patch sensors and actuators. 相似文献
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复合材料对称层合板特征值问题的灵敏度分析 总被引:2,自引:0,他引:2
由于复合材料层合板的横向剪切模量较低,因此基于克希霍夫理论而计算的层合板特征值及其灵敏度与实际情况相差较大。本文采用层合板的一阶剪切变形理论,将纤维铺设角、材料参数和从层合板的中面到第K层板上表面的距离ZK视为设计变量,研究了对称层合板特征值的灵敏度计算问题。 相似文献