一种道路用小型压电发电及储存装置的研究

为了收集并利用汽车通过公路时所产生的振动能量,设计了一种利用压电材料的正压电效应采集环境振动能量,把振动能转换成电能的道路用振动发电装置。为使压电材料和道路振动能巧妙结合从而吸收最大的外部能量,获得高的发电效率,进行了以下研究:分析了压电材料变形量对发电能力的影响,并设计了能找到压电材料产生最大电能的最小变形量的模型。通过实验分析压电片的联接方式对电能输出的影响,得到了以并联为主,串联为辅的混联电路模型。设计并制作了道路用压电发电装置模型,通过模拟实验测得其发电功率为0.061 2 W,电容储电功率为0.026 4 W,发电效率为14.42%,电容储电效率6.21%。     

传感器的低频特性对高冲击测试的影响研究

根据航天、航空环境中加速度的测试特点,对比分析了压电传感器和压阻传感器在高冲击环境下的测试性能。首先,通过对冲击信号进行建模,仿真分析了不同低频特性的加速度传感器对冲击信号测试的影响;然后,分析了压电、压阻类传感器的低频特性;最后,用冲击试验台验证压电传感器和压阻传感器在模拟的环境下的测试情况,得出低频特性好的传感器(压阻传感器)更适合在高冲击条件下的测量的结论。     

Mathematical Analysis of Piezoelectric Sandwich Torsion Transducers Based on the d36-Effect

In the present article, we analyze a d₃₆-effect piezoelectric torsion transducer following the Saint-Venant torsion theory taking the electrical field into account. A representation of the stress function, the electric potential, and the warping function are derived and solved with finite differences. Then, the one-dimensional governing equations at the structural beam level, including the constitutive relations as well as the balance equations for the dynamics of the transducer, are presented. The axial moment and the total charge are computed as functions of the rate of twist and the applied potential difference. As an example, a cantilevered transducer is studied.     

Exact 3D Thermoelectroelastic Analysis of Piezoelectric Plates through a Sampling Surfaces Method

The article focuses on the use of the method of sampling surfaces (SaS) to exact three-dimensional (3D) solutions of the steady-state problem of thermoelectroelasticity for piezoelectric laminated plates subjected to thermal loading. The SaS method is based on selecting inside the nth layer I_n not equally spaced SaS parallel to the middle surface of the plate in order to choose temperatures, electric potentials, and displacements of these surfaces as basic plate variables. This permits the representation of the proposed thermopiezoelectric plate formulation in a very compact form. The SaS are located inside each layer at Chebyshev polynomial nodes that improves the convergence of the SaS method significantly. As a result, the SaS method can be applied to 3D exact solutions of thermoelectroelasticity for piezoelectric laminated plates with a specified accuracy using the sufficient number of SaS.     

Thermal Buckling Analysis of Piezoelectric Functionally Graded Plates with Temperature-Dependent Properties

In this study, the thermal buckling analysis of hybrid laminated plates made of two-layered functionally graded materials (FGMs) that are integrated with surface-bonded piezoelectric actuators referred to as (P/FGM)_s are investigated. Material properties for both substrate FGM layers and piezoelectric layers are temperature-dependent. Uniform temperature rise as a thermal load and constant applied actuator voltage are considered for this analysis. By definition of four new analytic functions, the five coupled governing stability equations, which are derived based on the first-order shear deformation plate theory, are converted into fourth-order and second-order decoupled partial differential equations (PDEs). Considering a Levy-type solution, these two PDEs are reduced to two ordinary differential equations. One of these equations is solved using an accurate analytical solution, which is named as power series Frobenius method. The effects of parameters, such as the plate aspect ratio, ratio of piezoelectric layer thickness to thickness of FGM layer, gradient index, actuator voltage, and the temperature dependency on the critical buckling temperature difference, are illustrated and explained. The critical buckling temperatures of (P/FGM)_s with six various boundary conditions are reported for the first time and can be served as benchmark results for researchers to validate their numerical and analytical methods in the future.