scholarly journals Mathematical Modeling of an Active-Fiber Composite Energy Harvester with Interdigitated Electrodes

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
A. Jemai ◽  
F. Najar ◽  
M. Chafra ◽  
Z. Ounaies
Keyword(s):  
Finite Element ◽  
Energy Harvesting ◽  
Dynamic Behavior ◽  
Structural Model ◽  
Piezoelectric Materials ◽  
Fiber Composite ◽  
Interdigitated Electrodes ◽  
Active Fiber ◽  
Active Fiber Composites ◽  
Composite Energy

The use of active-fiber composites (AFC) instead of traditional ceramic piezoelectric materials is motivated by flexibility and relatively high actuation capacity. Nevertheless, their energy harvesting capabilities remain low. As a first step toward the enhancement of AFC’s performances, a mathematical model that accurately simulates the dynamic behavior of the AFC is proposed. In fact, most of the modeling approaches found in the literature for AFC are based on finite element methods. In this work, we use homogenization techniques to mathematically describe piezoelectric properties taking into consideration the composite structure of the AFC. We model the interdigitated electrodes as a series of capacitances and current sources linked in parallel; then we integrate these properties into the structural model of the AFC. The proposed model is incorporated into a vibration based energy harvesting system consisting of a cantilever beam on top of which an AFC patch is attached. Finally, analytical solutions of the dynamic behavior and the harvested voltage are proposed and validated with finite element simulations.

Analytical Solutions for Effective Axial Mechanical Properties of a Three-Phase Active Fiber Composite Model

2007 ◽  
Author(s):  
Davood Askari ◽  
Mehrdad N. Ghasemi Nejhad
Keyword(s):  
Mechanical Properties ◽  
Finite Element ◽  
Analytical Solutions ◽  
Fiber Composite ◽  
Fiber Composites ◽  
Orthotropic Materials ◽  
Exact Analytical Solutions ◽  
Active Fiber ◽  
Three Phase ◽  
Active Fiber Composites

Active fiber composites are among the many other components used in intelligent and smart composite structures which undergo mechanical deformation upon the application of external loads or electric fields. This work presents an analytical approach for derivations of exact solutions for the effective axial mechanical properties of active fiber composites with circular cross-sections, and while the properties of the constituent materials are considered to be generally orthotropic. First, exact analytical solutions of the effective longitudinal Young’s modulus and Poisson’s ratio are obtained for a three-phase composite cylindrical model composed of orthotropic materials. Next, Finite element analysis, as an alternative approach, is performed to numerically determine the effective axial properties of an identical three-phase composite cylinder. Finally, effective material properties obtained from analytical and finite element methods are compared to verify the derived analytical solutions. Excellent agreements are achieved between the results obtained from both techniques validating the exact analytical solutions.

scholarly journals Design, Analysis and Finite Element Modeling of Macro Fiber Composite Piezoelectric Materials

2020 ◽  
Vol 2 (2) ◽  
pp. 24
Keyword(s):  
Finite Element ◽  
Energy Harvester ◽  
Piezoelectric Materials ◽  
Fiber Composite ◽  
Electrical Response ◽  
Element Model ◽  
Ambient Vibration ◽  
Vibration Energy ◽  
Response Analysis ◽  
Vibration Energy Harvester

Vibration energy harvester has been paid a lot of attention by many researchers to transforming ambient vibration into electrical energy, which is normally utilized to develop wireless electronic sectors. The paper presents a finite element model (FEM) of a vibration energy harvester consisting of a bimorph electromechanical system (MEMS) generator. The model is used to simulate, and compare, the mechanical characteristics and electrical response of piezoelectric material results between the cantilever beam structure formed by laminating two piezoelectric layers on both sides of a Carbon fiber reinforced polymer (CFRP) substrate and Ti-6Al-4V substrate using ANSYS®19 R1. A set of numerical simulations has been carried out, and the results show that the comparisons of the harmonic response analysis seen change between the different substrates based on the bimorph piezoelectric MEMS generator.

A Comparative Finite Element Analysis of Residual Stresses in Active Fiber Composites With Embedded Metal-Core Piezoelectric Fibers and Macro Fiber Composites

Aerospace ◽  
2005 ◽  
Author(s):  
Davood Askari ◽  
Hiroshi Asanuma ◽  
Mehrdad N. Ghasemi-Nejhad
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Residual Stresses ◽  
Coefficient Of Thermal Expansion ◽  
Fiber Composites ◽  
Stress And Strain ◽  
Metal Core ◽  
Element Analysis ◽  
Active Fiber ◽  
Active Fiber Composites

Residual stresses are basically developed due to intrinsic and extrinsic strains that form during the processing of composite materials. The extrinsic strains can be determined using Coefficient of Thermal Expansion (CTE), material properties, geometry of the structure, and processing conditions. Finite Element Method (FEM) as an efficient alternative technique for stress and strain analysis of the micromechanical systems and structures, has been employed to numerically investigate the residual stresses developed in Metal-Core Piezoelectric Fibers (MPF) and Active Fiber Composites (AFC) (or Macro Fiber Composites (MFC)), during the processing. Here in this work, ANSYS Finite Element Analysis (FEA) software is used to develop three different 3-dimensional models for MPF and MFC structures and then each model is solved for strain and stress results. Next, the stress and strain components of these models are studied throughout the structures to identify the magnitude and type of the stresses and strains within the constituent materials and then compared.

Micromechanics of Longitudinal Mechanical Properties for Active Fiber Composites With Embedded Metal-Core Piezoelectric Fibers

Aerospace ◽  
2005 ◽  
Author(s):  
Mehrdad N. Ghasemi Nejhad ◽  
Davood Askari
Keyword(s):  
Mechanical Properties ◽  
Fiber Composite ◽  
Transversely Isotropic ◽  
Fiber Composites ◽  
Core Material ◽  
Metal Core ◽  
Element Analysis ◽  
Active Fiber ◽  
Active Fiber Composites ◽  
Piezoelectric Fiber

An analytical micromechanics approach is presented to model the effective longitudinal mechanical properties of Metal-Core Piezoelectric Fibers (MPF). The model assumes general orthotropic material properties for the piezoelectric as well as the core material. Next, the general orthotropic solution is reduced to transversely isotropic for the piezoelectric fiber and isotropic for the metal-core. This MPF system is also modeled using finite element analysis (FEA) and the results from the analytical solution and FEA are compared for verification purpose. Next, the Metal-Core Piezoelectric Fiber (MPF) is embedded inside a metal or a polymer and the resulting longitudinal mechanical properties of these Active Fiber Composite (AFC) systems are given analytically.

New Efficient Technique for Finite Element Modeling of Macro Fiber Composite Piezoelectric Materials

2020 ◽  
Vol 998 ◽  
pp. 221-226
Author(s):  
Diaa Emad ◽  
Mohamed A. Fanni ◽  
Abdelfatah M. Mohamed
Keyword(s):  
Finite Element ◽  
Piezoelectric Materials ◽  
Fiber Composite ◽  
Computational Time ◽  
Time Cost ◽  
Element Analysis ◽  
Element Mesh ◽  
Detailed Model ◽  
Macro Fiber Composite ◽  
Computational Time Cost

A lot of interest to simulate piezocomposite actuators with finite element method has been increased recently. However, there are still open questions regarding the modeling methodology, accuracy, and computational time cost. In this work, a new technique for modeling macro fiber composite piezoelectric actuator by finite element analysis is proposed. The presented technique models the piezocomposite actuator as a simple monolithic piezoceramic material with just two electrodes along its longitudinal extremes instead of using the actual large number of electrodes which results in very fine finite element mesh with high computational time cost. The proposed technique is validated successfully by comparing its results with those of the actual detailed model as well as with the published experimental results and manufacturer’s data.

Resonant Nonlinearities of Macro-Fiber Composite Cantilevers in Energy Harvesting

2017 ◽  
Author(s):  
David Tan ◽  
Paul Yavarow ◽  
Alper Erturk
Keyword(s):  
Energy Harvesting ◽  
Fiber Composite ◽  
Rectangular Cross Section ◽  
Electrical Power ◽  
Interdigitated Electrodes ◽  
Modeling And Analysis ◽  
Dissipative Effects ◽  
Macro Fiber Composite ◽  
Electrical Loads ◽  
Electrical Power Output

We explore the modeling and analysis of nonlinear non-conservative dynamics of macro-fiber composite (MFC) piezo-electric structures, guided by rigorous experiments, for resonant vibration-based energy harvesting, as well as other applications leveraging the direct piezoelectric effect, such as resonant sensing. The MFCs employ piezoelectric fibers of rectangular cross section embedded in kapton with interdigitated electrodes to exploit the 33-mode of piezoelectricity. Existing frameworks for resonant nonlinearities have so far considered conventional piezoceramics that use the 31-mode of piezoelectricity. In the present work, we develop a framework to represent and predict nonlinear electroelastic dynamics of MFC bimorph cantilevers under resonant base excitation. The interdigitated electrodes are shunted to a set of resistive electrical loads to quantify the electrical power output. Experiments are conducted on a set of MFC bimorphs over a broad range of mechanical excitation levels to identify the types of nonlinearities present and to compare the model predictions and experiments. The experimentally observed interaction of material softening and geometric hardening effects, as well as dissipative effects, is captured and demonstrated by the model.

Piezoelectric energy harvesting using macro fiber composite patches

2020 ◽  
Vol 234 (21) ◽  
pp. 4331-4349
Author(s):  
Marwa Mallouli ◽  
Mnaouar Chouchane
Keyword(s):  
Energy Harvesting ◽  
Epoxy Matrix ◽  
Composite Structures ◽  
Fiber Composite ◽  
Matrix Material ◽  
Interdigitated Electrodes ◽  
Piezoelectric Energy ◽  
Resonance Frequencies ◽  
Macro Fiber Composite ◽  
Tip Mass

Over the last decade, vibration energy harvesting has received substantial attention of many researchers. Piezoelectric materials are able to capture energy from ambient vibration and convert it into electricity which can be stored in batteries or utilized to power small electronic devices. In order to benefit from the 33-mode of the piezoelectric effect, interdigitated electrodes have been utilized in the design of macro fiber composites which are made of piezoelectric fibers of square cross sections embedded into an epoxy matrix material. This paper presents an analytical model of a macro fiber composite bimorph energy harvester using the 33-mode. The mixing rule is applied to determine the equivalent and homogenized properties of the macro fiber composite structures. The electromechanical properties of a representative volume element composed of piezoelectric fibers and an epoxy matrix between two successive interdigitated electrodes are coupled with the overall electro-elastodynamics of the harvester utilizing the Euler–Bernoulli theory. Macro fiber composite bimorph cantilevers with diverse widths are simulated for power generation when a resistive shunt loading is applied. Stress components in the Kapton layers, which are typically a part of any macro fiber composite patch, and in the bonding layers have been included in the model contrary to previously published studies. Variable tip mass, attached at the free end of the beam, is utilized in this paper to tune the resonance frequency of the harvester. The generated power at the fundamental short circuit and open circuit resonance frequencies of harvesters having three different widths is analyzed. It has been observed that higher electrical outputs are produced by the wider macro fiber composite bimorph using (M8528-P1 patches).

Sign in / Sign up

Export Citation Format

Share Document