International Journal of Application or Innovation in Engineering & Management (IJAIEM)
Web Site: www.ijaiem.org Email: editor@ijaiem.org, editorijaiem@gmail.com
Volume 3, Issue 8, August 2014
ISSN 2319 - 4847
Finite element modeling of a cantilever beam
bonded by piezoelectric material PZT5A and
a single degree of freedom elastic system for
energy harvesting applications
Yogesh S. Powar1, Prof. A.M. Naniwadikar2,
1, 2
Mechanical Engineering Dept.
Dr. J. J. Magdum College of Engineering Jaysingpur,India.
ABSTRACT
Vibration-based energy harvesting has received growing attention over the last decade. The research motivation in this
field is due to the reduced power requirement of small electronic devices, such as the wireless sensor networks used in
passive and active monitoring applications. The ultimate goal in this research field is to supply power to such small
electronic devices by using the vibrational energy available in their environment. The paper aims “to complete finite
element analysis of a cantilever beam having PZT5A patch with SDOF system for constant input amplitude”. The
results are verified with experimental results. This paper highlights on the energy harvesting of piezoelectric material
(PZT5A) by using single degree of freedom system to cantilever beam.
Keywords: piezoelectric material, SDOF, vibrational energy.
1. INTRODUCTION
In last few years it has been seen that there is increasing demand of low power and portable energy sources due to the
development of portable electronic devices. The portable energy sources must be associated with environmental issues and
imposed regulations. This demand supports the research in the areas of portable energy generation methods. In this scope,
piezoelectric materials become a strong candidate for energy generation and storage in future applications. The piezoelectric
effect is a reversible process. In this the internal generation of electrical charge is resulting from an applied mechanical force
and the reverse piezoelectric effect is that internal generation of a mechanical strain resulting from an applied electrical
field. It not only fulfills the growing needs of renewable sources of energy but also propose several potentially inexpensive
and highly effective solutions. Because of their electromechanical coupling characteristics, piezoelectric material can be used
for vibration control, but the capability of transferring energy from the mechanical to the electrical domain can be exploited
to store vibrational kinetic energy into circuitry elements or batteries. Piezoelectric material reduces the complexity of
wiring. Today there is increasing popularity of wireless networking, piezoelectric material fulfill the demands of wireless
networking as it is charged without electricity. It is eco-friendly and it reduces the negative impact on environment.
2. Proposed Layout
PZT5A
Figure 1 Cantilever beam with PZT5A patch and SDOF
2.1Three Dimensional Model
Size of the substrate (AL) plate- 300x50x3mm
Size of Piezoelectric Plate-100x50x2mm
Volume 3, Issue 8, August 2014
Page 52
International Journal of Application or Innovation in Engineering & Management (IJAIEM)
Web Site: www.ijaiem.org Email: editor@ijaiem.org, editorijaiem@gmail.com
Volume 3, Issue 8, August 2014
ISSN 2319 - 4847
2.2 Properties of Aluminum
Density
= 2700 kg/m3.
Young’s Modulus = 70 GPa.
Poison’s Ratio
= 0.34
2.3 Spring Stiffness
K =2.15 X 1013 N/mm
2.4 PZT-5A Properties are referred from [9] and used in ANSYS
Density of PZT-5A = 7750 kg/m3
PZT-5A Dielectric Permittivity Matrix at Constant Stress [ ]
PZT-5A Elastic Compliance Matrix [s], 10–12 m2/N
PZT-5A Piezoelectric Strain Matrix [d], 10–10 C/N
3. FINITE ELEMENT MODELING
In this section, a finite element model is developed in ANSYS software to study the effect of SDOF system for energy
harvesting and validate with experimental results. Figure 2 shows the meshed model of aluminum beam with PZT5A
material.
Figure 2 Meshed model in ANSYS
Figure 3 shows the finite element model of piezoelectric material combined with SDOF, in which single patch of PZT5A
material is attached on the top of beam and the thickness of the adhesive is very small so it is neglected. The 8-node
hexahedral coupled-field element SOLID186 is used for the PZT layers. The 8-node linear structural element SOLID226 is
used for the aluminum beam. The point element MASS21 is used for the lumped mass (M) of the SDOF system. The springdamping element COMBIN14 is used for the spring(K) of the SDOF elastic system. The piezoelectric circuit element
CIRCU94 is used to model the load resistance for generating voltage, current and power outputs.
Volume 3, Issue 8, August 2014
Page 53
International Journal of Application or Innovation in Engineering & Management (IJAIEM)
Web Site: www.ijaiem.org Email: editor@ijaiem.org, editorijaiem@gmail.com
Volume 3, Issue 8, August 2014
ISSN 2319 - 4847
Figure 3 Finite Element model with SDOF system
Figure 4 shows the NODAL SOLUTION of a finite element model in ANSYS by giving input constant ampitude of
magnitude 20 μm.
Figure 4 NODAL SOLUTION of a finite element model in ANSYS at 80Hz
Figure 5 shows the voltage-frequency graph of finite element model in ANSYS
Figure 5 Voltage-Frequency graph of finite element model in ANSYS
4.EXPERIMENTAL STUDY
4.1 Experimental Setup
The experimental setup is prepared as shown in figure 5. In that aluminum beam is used as a cantilever and PZT5A patch
is attached at the tip of beam on top while at the other end a rod is bolted. The top of this rod is fixed in the beam while the
bottom end is attached to the exciter of capacity 100N. By using exciter the model is excited at different frequencies with
constant amplitude of 20µm which is adjusted by using FFT analyzer.
Figure 6 Experimental Setup
Volume 3, Issue 8, August 2014
Page 54
International Journal of Application or Innovation in Engineering & Management (IJAIEM)
Web Site: www.ijaiem.org Email: editor@ijaiem.org, editorijaiem@gmail.com
Volume 3, Issue 8, August 2014
ISSN 2319 - 4847
4.2Results and discussion
Figure 7 shows the graph of Voltage-Frequency variation at constant amplitude.
Figure 7 Graph of Voltage-Frequency variation at constant amplitude
5.CONCLUSION
A study was carried out to verify the results of voltage generation of piezoelectric material (PZT5A) subjected to SDOF
system. The results of finite element modeling are compared with experimental results & good agreement is found in
between them.
REFERENCES
[1] ISRN material science volume 2012, article ID 921361.
[2] Wang et al. / J Zhejiang University-Science (Applied Physics &Engineering) (An energy harvester combining a
piezoelectric cantilever and a single degree of freedom elastic system)2012-13(7):526-537C. De Marqui Junior et al. /
Journal of Sound and Vibration (An electromechanical finite element model for piezoelectric energy harvester plates)
327 (2009) 9–25
[3] Jiyuan wang Excerpt from the Proceedings of the COMSOL Multiphysics User's Conference 2005 Stockholm
[4] Smart Mater. Structure. 18 (2009) 115025
[5] J. Schoeftner, G. Buchberger/Engineering Structures (A contribution on the optimal design of a vibrating cantilever in
a power harvesting application – Optimization of piezoelectric layer distributions in combination with advanced
harvesting circuits) 53 (2013) 92–101
[6] Ming li, yumei wen, ping li, jin yang, xianzhi dai / Sensors and Actuators A (A rotation energy harvester employing
cantilever beam and magnetostrictive/piezoelectric laminate transducer) 166 (2011) 102–110
[7] Levent beker, haluk külah, ali muhtaroğlu (Piezoelectric Cantilever Prototype for EnergyHarvesting in Computing
Applications)978-1-4673-0465-8/11/$26.00 ©2011 IEEE
[8] A. Perry and C.R. Bowen (FINITE ELEMENT MODELLING OF 3-3 PIEZOCOMPOSITES)
[9] Department of Materials Science & Engineering, University of Bath, Bath, Somerset, UK, PII S1359-6462(99)00249
AUTHOR
Yogesh S. Powar received B.E. degree in Mechanical engineering from Dr. J.J. Magdum College of
Engineering, Jaysingpur in 2010 and pursuing M.E. from Shivaji University. During 2012-14 he is doing
research in machine design field. He is now with Sanjay Ghodawat Polytechnic, Atigre.
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