Science topic

Piezoelectricity - Science topic

Piezoelectricity is the charge that accumulates in certain solid materials (notably crystals, certain ceramics, and biological matter such as bone, DNA and various proteins) in response to applied mechanical stress.
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Dear researchers,
My research area is related to the development of metallic composites. I am switching to sensor development. Basically, I will work on the development of advanced materials for sensor applications. I need your guidance, suggestions, and ideas. I am also looking for collaboration in this area.
Looking for your valuable replies.
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We don't have any sensor development lab right now.
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Hello dear researchers
I want to calculate the piezoelectric properties of a solid using wien2k and castep/materials studio. Please, I need some advice on how I can calculate the properties and the necessary packages. If there is another method, please feel free to mention it.
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Welcome
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My main research is electrospinning of PVDF as piezoelectric sensors. According to the description in papers, I "Used PI/PET film as the substrate, pasted conductive tape as one side electrode, connected the external wire, added PVDF film, and then pasted the conductive tape on top of the PVDF film as the other side electrode, connected the external wire, and finally used PDMS glue for packaging". But I replaced the PVDF fiber with other non-piezoelectric polymers such as PAN, TPU, etc. The PAN sensor obtained by this preparation method can also detect electrical signals under deformation. At the beginning, I thought it might be the reason of the conductive glue, so I used silver glue instead of the conductive tape as the electrode, but the sensor made of PVDF and PAN fiber film can still have electrical signals under deformation, which cannot reflect the piezoelectric characteristics of PVDF.
So I come here for more detailed information about preparing the PVDF Piezoelectric Sensor, such as what is the best material or method to prepare the electrode, how to reduce the air between different layers of the sensor.
Thank you very much!
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Hi Woo Hyunsup,
-You can directly deposit gold on both sides of PVDF free-standing film or paste aluminum foil on both the side and then encapsulate it with PDMS stamp. For connections you can use thin copper wire pasted over electrodes.
- You will definetly get signals out of non piezoelectric materials such as PAN but that signals are not piezoelectric. Those signals are called triboelectric signals and arises because of friction.
Thanks and Regards
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My main research is electrospinning of PVDF as piezoelectric sensors. According to the description in papers, I "Used PI/PET film as the substrate, pasted conductive tape as one side electrode, connected the external wire, added PVDF film, and then pasted the conductive tape on top of the PVDF film as the other side electrode, connected the external wire, and finally used PDMS glue for packaging". But I replaced the PVDF fiber with other non-piezoelectric polymers such as PAN, TPU, etc. The PAN sensor obtained by this preparation method can also detect electrical signals under deformation. At the beginning, I thought it might be the reason of the conductive glue, so I used silver glue instead of the conductive tape as the electrode, but the sensor made of PVDF and PAN fiber film can still have electrical signals under deformation, which cannot reflect the piezoelectric characteristics of PVDF.
So I come here for more detailed information about preparing the PVDF Piezoelectric Sensor, such as what is the best material or method to prepare the electrode, how to reduce the air between different layers of the sensor.
Thank you very much!
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Hello Jiayi Yin
Did u find the solution to reduce the air gap between layers in piezoelectric sensor?
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Hi,
I have a thin layer of piezoelectric material sandwiched between relatively thin film of two distinct metals. I am experiencing few problems while setting up the simulation.
First, the material properties for metals require coupling matrix even though they are not piezoelectric materials.
Second, comsol prefers stress-charge form parameters. How do I change this setting to strain-charge form so, I won't have to change elasticity to compliance matirx and d-matrix to e-matrix?
And last, how do I know whether the relative permittivity on material datasheet is given at constant stress or constant strain?
Will really appreciate your time while answering any or all of my queries. Thank you in advance!
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Hi Aashish,
1. Select only piezoelectric material in the Piezoelectric material domain selection in the solid mechanics module, therefore all remaining materials will be considered as a linear elastic material.
2. solid mechanics module < piezoelectric mmaterial< in settings of piezoelectric material, change the constitutive relation to stress charge or strain charge form
3. When you select the stress charge form, the material's relative permittivity auto selects the constant strain and If you select the strain charge form, the relative permittivity auto selects the constant stress values.
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Hi, I am working on piezoelectric energy harvester simulation. I would like to know why I couldn't put voltage coupling boundaries condition in the modal (once i put in, the error shows up). Thus i deleted this condition. But i am not sure if it is correct or not. Could anyone help me have a look this? Many many thanks. 
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Hey were you able to solve this issue , I am facing the same problem .
Thanks
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Hello and have a good time
We have a viscous polymeric material that is used as a thin coating on the ceramic part of piezoelectric disks in shock sensors.
This material helps to reduce noise and increase the sensitivity of the sensor.
We separated the material using heat and sent it for FTIR testing. Experimental results show that the main chemical composition of the substance is triacontane. Which is used in making wax paraffins. What is the reason for the performance of this material on the sensitivity of the sensor? Also how can I find these materials commercially
You can see it in the attachment
Thank you very much
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Hello
I am working on a piezoelectric energy harvesting system consisting of a rectangular piezoelectric cantilever. As you can see, the output voltage of the piezoelectric cantilever is saturated/cut with increasing input acceleration in the experimental results.
But the output voltage is sinusoidal in COMSOL Multiphysics simulations.
I am looking for reasons for the difference but I didn't find much.
What is the reason for the difference?
*************
The transient response of the output voltage has been added.
Also, a picture of a typical piezoelectric cantilever has been added [1].
[1] H. Li, C. Tian, and Z. D. Deng, "Energy harvesting from low-frequency applications using piezoelectric materials," Applied physics reviews, vol. 1, p. 041301, 2014.
Wishing you health and success
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please check the impedance mismatch. Also Since check the time constant of the circuit.
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I am using the mechanical module in ANSYS workbench to simulate a cantilever beam. The system is simple, a cantilever beam of dimensions 70x50x0.7 mm with a point force applied at the center of the top edge of the free end of the beam.
As the direct piezoelectric effect indicates, when a mechanical load is applied on a piezoelectric material it will produce an electrical signal. I'm interested in the voltage that will produce the beam by the force applied. The manuals says that the coupling equation is the following
{D}=[e]T {S} + [ εS] {E}
where D is the electric displacement or electric flux density, e is the piezoelectric stress matrix,
ε is dielectric matrix, and E is electric field.
I would like to know how ANSYS relates the electric displacement to the voltage result. Does it use a similar equation to the following?
D=Q/A=C*V/A, where C is capacitance, V is voltage, and A would be area of electrodes
If that is the case, how is it calculating capacitance? and if not, how does it gets the voltage?
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hi, you can use transient analysis and set ext piezo and mems also. the ansys uses deformation to calculate the voltage, for example the ansys may use the equation V=(g33*F*t)/A, Where you can put F=kx (hooks law), where x is deformation, g33 is voltage(V) response as a function of strain applied, A is cross section area and t is thickness of your film
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I am trying to run a simulation in which I need 2 modules together: the MEMS Module which deals with the piezoelectric effect by coupling both the Solid Mechanics (solid) and Electrostatics (es) interfaces, and the Semiconductor Module. So far both modules are working independently, and I could not find a suitable method to integrate them together.
My research is regarding the doping effect on piezoelectric potential output and properties. So I need the equations of both modules to be able to cross-communicate to cover all theoretical aspects of this simulation. I tried to change the equations of the semiconductor module but was not successful.
So my question is, what are all the steps needed so that I can change the COMSOL setup to combine both modules (MEMS and Semiconductor) for them to cross-communicate and simulate successfully?
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Ref this document
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Magnetoelectroelastic solids show both piezoelectric effect and magnetostrictive effect. How can I couple piezoelectric and magnetostrictive multiphysics in COMSOL/ANSYS?
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Thank you Martin Rotter
As per my knowledge, McPhase is not based on the FEM approach.
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My piezoelectric nanofibers are BNT [(Bi0.5Na0.5)TiO3] and were synthesized by hydrothermal method with dimensions around 100nm in diameter and the length of several micrometers. 
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electrospinning the fiber on Pt/Si substrate and post-annealing
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As we know, the triboelectric devices and piezoelectric devices are broadly used in energy harvesting and sensing. What're the each advantages of them for energy harvesting and sensing?
Thanks a lot!
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I agree with Xu Liu. TENG generates high voltages and low currents whereas PENG generates low voltage and comparatively higher current. Construction wise TENG is much simpler. More research is required to enhance its performance and hence there is a great opportunity for researchers.
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I'm trying to do a simulation of conventional piezoelectric energy harvester (Cantilever beam harvester) in Abaqus. I want to consider the base acceleration and frequency sweep both either in harmonic analysis or dynamic analysis. Is there anyone can assist me on this please? Thank you in advance.
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It is better to start from the theoretical basis of this topic, means starting from the Fourth Order PDE.
Regards,
Emad
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Do we need a smoother thin film of Piezoelectric membrane material in the PMUT device performance? is there any dependence of resonant frequency on the roughness of piezoelectric membrane in PMUT?
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The resonant frequency depends on the geometry of the piezoelectric material. The thickness mode resonance frequency as such depends on the thickness of the specimen. If variation in the thickness of the film is not significant, you will get a clean resonance impedance response, otherwise the response will have kinks. The resonant frequency however will not change significantly even for the later case.
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what influence on the level of power given by a piezoelectric sensor.
Is the frequency , or the input signal level have influence?
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The core element of the transducer is piezoelectric material. The frequency of the piezoelectric material is related to its thickness. The smaller the thickness of the piezoelectric material, the higher the frequency of the piezoelectric transducer
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Want to use PVDF as a flexible temperature sensor due to its excellent flexibility and pyroelectric properties. But at the same time, it is piezoelectric too.
When using as a temperature sensor this piezoelectric behavior may contribute in the output voltage when stretched. In order to avoid this, is there any specific force up to which we can stretch the film without piezoelectric characteristics coming into picture, and which will not affect the voltage value?
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I think there are much easier ways to measure temperature than using PVDFs. As you know piezoelectric sensors have a strong dependency to temperature, but you will have to compensate somehow the generated charges linked to mechanical strains such as vibrations, deformation or elongation …
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Why the g-C3N4 material exhibits piezoelectricity?
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Due to its Physical property of the material like ( bandgap, strong polarizability )
I think this G-C3N4 will have semiconductor property.
Check its space group. it has any ferroelectric nature.
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Hello,
Can piezoelectric coefficients of thin films can be measured without meter?
Thanks
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Thanks for the response. I already have quote from that company, its over $4500.
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I have a device with confriguration Au/PVDF/Au. The connections are taken from the gold electrode using copper tape and over that I have soldered copper wire and finally they are connected to DSO. When I am tapping the device (on gold electrode), then gold electrode is behaving as one tribo layer and my hand is behaving like a ground. So, now the device is behaving like a single-electrode TENG. How can I separate out piezosignal out of this tribo signal? If anybody have any idea then please share.
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your body is not always ground, it could have a charge. As our body stores charge like a capacitor, there should be always a device that gives a tapping movement. it should not touch with any other materials or a material that is near to zero in triboelectric series like wood. That is the only solution to separate your signal from each other( if it is an independent tapping system without the involvement of the body). As our body skin has highly negative in triboelectric series. in the link, I have sent you our independent characterization device that has the ability to characterize samples without the involvement of the body.
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Can anyone tell me how many power/area could I collect with a ceramic piezoelectric disc? Or where can I find it? I tried to seach it but I didn't find it. I need a paper or document with that information
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The energy you may convert from mechanical to electrical is given by the kopupling factor of that specific piezo material.
The electromechanical coupling factor k is indicating the effectiveness with which a piezoelectric material converts electrical energy into mechanical energy, or converts mechanical energy into electrical energy.
You may find some more details on my website:
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I need to clarify that is 1 pm/V = 1pC/N?
Why there are two units?
Are the methods to measure the piezoelectric coefficient in the two units, different?
Kindly help!
Thank you.
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For piezoelectric materials, there are piezoelectric effect and inverse piezoelectric effect.
Piezoelectric effect means if we give a force to piezoelectric materials then the charges will be generate in the surface of materials, so the "pC/N" is used to describe this force to charge "piezoelectric effect".
In contrast, the inverse piezoelectric means if we give a voltage to piezoelectric materials then it will produce strain, so the "pm/V" is used to describe this voltage to strain "inverse piezoelectric effect".
The "inverse piezoelectric effect" equal to the "piezoelectric electric effect" theoretically.
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The piezoelectric charge coefficient (d) considers the directions of the applied force and polarization. However, ZnO is not a ferroelectric material, so I can't pole it with an external electric field. Therefore, how can I know the direction of the already existing dipoles to determine d33? I plan on using the Berlincourt method.
Moreover, I want to produce a Polyurethane/ZnO composite to enhance the material's flexibility. Is there any recommended synthesis method to this case?
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Oriented ZnO thin films made by sputtering are piezoelectric, you don't need electrically pole them like normal ferroelectric piezo-elements like PZT. PZT thin films are normally polycrystalline, hence you need to pole them. There are many papers in the literature on the measurement of piezoelectric coupling from ZnO films, and the measurement of piezo coefficient.
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Hello,
One of my colleagues is working with piezoelectric components and couldn't find the shock response spectrum for various piezoelectric components. Can anyone please share your idea to deal with the calculation process of shock response spectrum (srs) of piezoelectric components? However, any informative links that contain useful resources or details will be very helpful.
Thank you for your time and guidance.
Best wishes,
Faishal Rahaman
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I have a RG write-up for the impulse excitation of a piezoelectric shock sensor (PSS), which you may find of interest for your current problem, see, . I just uploaded this Method today, 3/2/2022. I hope this helps.
Regards,
Thomas Cuff
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I want to maximize the resistance and capacitance of my AlN piezostack without sacrificing (too much) of my piezoelectric coefficient's value (d33). I am depositing my AlN via reactive sputtering.
To that end, would it be a good idea to have a multilayered stack, alternating between thick high crystallinity AlN layers and thin amorphous AlN layers?
So far in my search through literature, I have only found a single mention of AlN piezoelectrics needing to be a homogenous layer, and this was without evidence or a proper explanation.
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Hi Franco,
To my best knowledge, both crystalline and amorphous AlN films are very insulating. I am curious about if you already measured resistance and capacitance of the crystalline and amorphous films?
I think stacking thick crystalline AlN layers and thin amorphous AlN layers (c-AlN/a-AlN films) can probably deteriorate piezoelectric properties of AlN films. As you know that (002)-oriented films are required to obtained piezoelectricity in AlN. We did not have results on c-AlN/a-AlN films but we reallized that the amorphous AlOxNy layers at the beginning of film growth degraded piezoelectric response. However, you could find an acceptable balance between piezoelectric response and resistance/capacitance by playing around with those thicknesses.
By the way, here are our papers related to AlN film by ALD if you would like to take a look: 10.1063/5.0011331 and 10.1021/acsami.1c08399
Hope it helps.
Regards,
Tai
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Recently, I was trying to study PVDF-based piezoelectric sensors and there were some problems during the test. The device structure is PET/Ag NWs / PVDF/Ag NWs /PET, I used resonator to generate a periodic force and it was monitored by a force sensor, the piezoelectric device was attached to the Al substrate. Here are the specific questions:
1. The open circuit voltage signal generated by the device is different in the case of forward and reverse connection. The voltage in the forward connection is much greater than the reverse connection. In the case of a forward connection, I just thought that the rod of the resonator and the upper electrode constitute a triboelectric system to generate triboelectric charge to affect the open circuit voltage. But, I did not find a suitable solution.
2. When I fabricated a PET/Ag NWs / PI/Ag NWs /PET device, a voltage of several hundred millivolts still existed during the test.
I'm very confused and I hope someone can help me solve the probelem, thanks!
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I have attached a photo of the setup. The force is 30 N.
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Nano piezoelectric or airopiezoelectric or thermal generator
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Considering the piezoelectric materials, Lead Zirconate Titanate (PZT) Nanoparticles seem like an appropriate choice; their piezoelectric constant is higher than other groups of smart materials.
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We recently installed a DC electrical poling system to impart piezoelectric properties to thin polymer films (thickness range:0.1mm). In a test jig, when I apply DC poling voltage, the film suddenly breaks, and the machine trips because of increased leakage current. It is a thin PVDF film with a silver paste coating on both sides.
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The contact poling what you are trying is also a very good technique for poling if you don't have the corona poling facility.
From my experience, I will suggest that
1. Film thickness is fine, it should be dense as said by Abhishek Sasmal because airgap leads to earlier breakdown.
2. both the surfaces of the film should have a conductive coating (may be silver paste or thermally evaporated coating)
3. Conductive coating should be such that the conductive area should be less than the whole film area. e.g. if the sample is circular, the radius of the conductive coating area must be less than the sample radius on both sides.
4. Obviously check for continuity before the poling. (it should not be conductive across the thickness)
5. After loading the sample, the voltage (field) should be increased very slowly to check the breakdown. And below that voltage, it should be poled.
6. Temperature should not be very high (less than 80 degree C as per literature) and uniform heating is needed. First, heat the Silicon oil and stir it for at least 10 min for uniform heat distribution.
7. The contact of the poling unit should not be so sharp that it may puncher due to pressure at the same point
N.B. Always applied voltage in the case of corona poling is higher as compared to contact poling.
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When I was reading "Handbook of Advanced Dielectric, Piezoelectric and Ferroelectric Materials: Synthesis, Properties and Applications", I saw that some graphs about PMN-PT. d33, Pr and dielectric constant decreases as the grain size decreases. What is the reason of this?
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Does any teacher have the literature or MATLAB code for using velocity feedback and LQR to control piezoelectric beam, plate, and shell? Can you share it? Much of the literature on control cannot be reproduced without parameters
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Thank you very much for helping me
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The cantilever is trapezoidal shaped with non uniform substrate thickness. Piezoelectric layer, and electrode layers are uniform. I want to learn the the possible fabrication steps such kind of cantilever.
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Dear Anand, I am not sure to understand your question, but the steps might be:
- build the rod
- rectify if necessary the surface where you want to create your piezo substrate,
- bond the piezo layer (a ceramic or piezo-composite plate? Film?) and the electrodes, if not already done by the manufacturer,
- bond insulant layers where necessary,
- bond the piezo-assembly to the rod...
If you have to heat the sample during the bonding process, be careful to not exceed the depolarization temperature of your piezo-material!
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Based my understanding, sono-catalysis is utilizing ultrasonication to boost the enlarged surface area and promote the multiple phase catalytic reaction, while the piezo-catalysis is more like to form a internal electrical field and using its specific piezoelectric property to catalysis.
Is that correct? And is there coincidence between this two catalytic theories? Thank you.
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Hi Yue,
Thanks for reaching out and proposing the question. However, I'm sorry that I'm not the author of this article, so I'm unable to answer this question.
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I would like to simulate a piezoelectric harvester (figure 1) and perform a transient analysis in a bimorph piezoelectric beam. I know how to define piezoelectric material, but I'm having some problems with the boundary conditions. I coupled and connected the top and bottom VOLT DOF to the resistor and also ground the middle DOFs (figure 2). I tried to apply a harmonic base excitation (displacement or acceleration) at X=0 (figure 2) using the 'D' command and perform a 'FULL' transient solution, but the results for the voltage at one of the resistor nodes (figure) seems incorrect. Any help with what may be wrong or example on how to apply the base excitation would be highly appreciated. Thanks!
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hi, you should first solve modal and then you have to connect it to harmonic response solver in Ansys.
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I am modelling of piezoelectric material bonded on the host structure & correspondingly I have to plot electrical conductance vs frequency plot. Similar research has been done on Ansys apdl but since ansys apdl & Ansys workbench are bit different, thus I am not able to get that plot. I would be very thankful if any help can come from anywhere.
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Ansys Workbench is just a new interface of ANSYS APDL. At the end of the day, the model you make in workbench is going to be translated into APDL commands and ANSYS solver will solve it.
If you already have an example of your choice done in APDL, then you need to look at the APDL code and then select the ones that are related to defining material properties and BCs and then insert these commands into Workbench by means of command snippets and solve your model. You must get exact same result if you use identical geometry and mesh!!
Even, the ACT that Tejas Shelgaonkar was referring to does the same thing, it is only going to add same APDL commands into the code that will be sent to the solver. Basically, this ACT makes modeling of MEMS a bit easier. Long story short, if you know how and where you insert command snippets in Workbench you will get same results. I mean, if you could not get this ACT, you are still able to perform the analysis you want.
Below, I shared command snippets related to a Piezoelectric project that completed a few years ago in workbench. The mesh I used in this project was a HEX mesh and for that reason I used Solid226.
Defining material properties:
et,matid,SOLID226,1001
TB,PIEZ,matid
TBDATA,2,-4.1
TBDATA,5,-4.1
TBDATA,8,14.1
TBDATA,10,10.5
TBDATA,15,10.5
TB,DPER,matid
TBDATA,1,7.124E-9,5.841E-9,7.124E-9
MP,RSVX,0
MP,RSVY,0
MP,RSVZ,0
Boundary conditions:
!Displacement
d,End,ux,0
d,End,uy,0
d,End,uz,0
!Voltage
CP,NEXT,VOLT,Bot_Piezo $ d,Bot_Piezo,VOLT,0
!Coupling
CP,NEXT,VOLT,Mid_Piezo
Hope this answer helps!!
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I am looking for information on some kind of actuator which can produce about 1 mm displacement while consuming low power, was thinking of piezoelectric ones as they can have "ms" response time. Any leads much appreciated.
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Amplified Piezoelectric actuators are commercially available. You can select based on your requirement.
Few publications with different configurations
1 Design, fabrication, and testing of flexurally amplified piezo actuator
2 High frequency, large displacement, and low power consumption piezoelectric translational actuator based on an oval loop shell
3 New “HAPA”, “FTA”, and “HD-FTA” Piezoelectric Actuators
Many publications are available that you can get it on search
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Hi all.
I am performing a 2D wave propagation in time domain using piezoelectric effect of structural mechanics module.
I want to apply a Hanning window function as voltage to excite my PZT. I have apply my excitation signal as follows: sin(2*pi*fo*t)(t[1/s])
Could anyone tell me how to apply this input excitation signal to get appropriate result. Please find the attachment and kindly help me to get the correct expression of excitation signal.
Many Thanks
Himanshi
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This may occur in COMSOL because the unit is inconsistent with the preset, or the variable is not defined. You'd better check your settings carefully.
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In piezoelectric harvesting, mechanical energy converts into electrical energy . up to date what is the maximum output voltage which got generated using piezoelectric principle or piezo electric materials.?
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Voltage = (Piezo. charge coeff. / Dielectric constant) * Applied stress * thickness
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Dear colleagues,
Could we use scanning electron microscopy for investigation of the surface morphology of piezoelectric ceramics? May there arise some problems with piezoelectric effect during microscopy? Could we prevent such problems if we use conductive coatings and supports?
I would be grateful for your assistance
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Dear colleague,
SEM analysis of piezoelectric ceramics presents similar problems as most electrically insulating samples, mostly related to charging. This can indeed be efficiently solved by using conductive coatings (e.g. C or Au), as you noted in your question. Any specific challenges related to, e.g., dimensional changes in the sample due to the piezoelectric response to the charging will then be solved at the same time.
On the other hand, the use of low vacuum, which is another common approach to reducing charging of samples, may be less suitable for piezoelectric materials, since there may be some residual charging that can result in a piezoelectric response, depending on the sensitivity of the material.
Below is an example of a paper where SEM was successfully used the analyze surface morphology and cross section of a piezoelectric material.
I hope this answers your question.
Best,
Asbjørn
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In a mathematical analysis of piezoelectric models, we use the terms "the electrically open and short circuit case" for which we have some mathematical definition as well.
What is the physical significance of these boundary conditions in making sensors and other devices?
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Hi Sonal Nirwal,
The surface is metallized (short circuit (CC)): corresponds to the vanish of the electric potential.
The surface is non-metallized (open circuit (CO)): corresponds to the vanish of the surface charge density.
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We are looking for a reliable provider or vendor, that could provide us a technical and financial offer for piezoelectric transducers.
These transducers will be utiliezed for energy harvesting applications and experimentations.
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First, I want to know if Lithium Niobate is at a default orientation of 36 degrees? I am also looking for a resource to identify their young's modulus (anisotropic) and their stress matrix.
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You can validate your findings by comparison with the available literature, otherwise, you have to report your results by peer review process through a paper. Good luck
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Currently, I am working on LiNbO3 and LiTaO3 materials. Its relative properties of elastic, permittivity, and stress can be extracted for various orientations of cut (128/36 degrees) using the BOND method. I have extracted it for various orientations using MATLAB code. But, how these data can be validated?
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The only way is to compare with the available literature, if not enough data is found, you have to prove your findings and convince your peers through peer-reviewing ...
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Sir,
We are trying to set up a photo-acoustic spectrometer in our lab. We need the details about the specifications and manufacturers of the piezoelectric detector required for the pulsed photo-acoustics in liquids.
Thank you
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Electret microphones by Knowles will be useful.
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I have two equations for nonlinear piezoelectric energy harvester.
Mechanical domain:
𝑞̈(𝑡)^2+𝜁𝜔𝑞̇(𝑡) + 𝜔^2𝑞(𝑡)+Xθ ̈ - 𝜃𝑣(𝑡) + 𝜕𝑈𝑚⁄𝜕𝑞(𝑡) = −𝛤𝑧̈(𝑡)
Electrical domain:
𝐶𝑝𝑣̇(𝑡) + 𝑣(𝑡)/𝑅 = 𝜃𝑞̇(𝑡)
harmonic excitation terms
𝑞(𝑡) = Qe^j𝜔t, z(t) = Ze^j𝜔t, 𝑣(𝑡) = Ve^j𝜔t, these terms and its derivative are substituted in the above two equations.
(-𝜔^2Q+𝜁𝜔𝑞j𝜔 + 𝜔^2Q−𝜃V) e^j𝜔t +Xθ ̈ + 𝜕𝑈𝑚⁄𝜕𝑞(𝑡) = −𝛤(-𝜔^2Z)e^j𝜔t
After substitution, the nonlinear term (𝜕𝑈𝑚⁄𝜕𝑞(𝑡) - nonlinear magnetic force) and centrifugal force term (Xθ ̈ ) are there. We cannot able to cancel the harmonic term e^j𝜔t because of the presence of the nonlinear term and centrifugal term.
(-𝜔^2Q+𝜁𝜔𝑞j𝜔 + 𝜔^2Q−𝜃V) e^j𝜔t = −𝛤(-𝜔^2Z)e^j𝜔t
(-𝜔^2Q+𝜁𝜔𝑞j𝜔 + 𝜔^2Q−𝜃V) = −𝛤(-𝜔^2Z) (1)
Without that nonlinear term, we can able to cancel the harmonic term e^j𝜔t. Then get one equation to solve.
Similarly,
(𝐶𝑝j𝜔V + V/𝑅)e^j𝜔t = 𝜃j𝜔Qe^j𝜔t
(𝐶𝑝j𝜔V + V/𝑅) = 𝜃j𝜔Q (2)
solving (1) and (2) we able to get Voltage expression and displacement expression.
Similarly, how to get voltage and displacement expression for the nonlinear piezoelectric energy harvester with that nonlinear term?
Tell me suggestions regarding this.
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I guess you can search for approximate solution as just a sum of first and third harmonic.
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Hello everyone,
I want to know during PLD, where from bound charges come at the surface of ferroelectric materials? I want to know their origin, their charge either positive or negative, and their screening process (i.e. how to screen) and their effect on polarization of material. Moreover I also want to know what is depolarizing filed and what is its origin and how it could effect ferroelectric materials? A good ferroelectric material should have high depolarization field or low and why?
The last thing I want to know that these bound charges/depolarization field could exist only in PLD film preparation or also can be in hydrothermal/solgel film synthesis ?
Kindly anyone who is expert explain it.
Thank you
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Hello,
First of all, the bound charges are inherently generated by the ferroelectrics, by its definition, so I guess what you ask is the origin of screening charges. Screening charges comes from band bending, surface reconstruction, and absorption, etc, their characteristic dynamics are diverse.
If the bound charges are not fully screened, then comes the depolarisation field. Usually this leads to domain reconfiguration. The ferroelectrics will reduce its depolarisation field to reach minimum energy. So it should be not large if the system is stable, but it is not a criteria of whether it is good or bad.
Screening process do exist in all the preparation techniques.
Please refer this review for details.
Kalinin, Sergei V, Yunseok Kim, Dillon D Fong, and Anna N Morozovska. “Surface-Screening Mechanisms in Ferroelectric Thin Films and Their Effect on Polarization Dynamics and Domain Structures.” Reports on Progress in Physics 81, no. 3 (March 1, 2018): 036502. https://doi.org/10.1088/1361-6633/aa915a.
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Hello there! I'm new in using Ansys APDL. I'm trying to do the modal analysis of a simple unimorph piezoelectric cantilever beam, but the result is not what i expect to achive.
I'm wondering that there are some inputs that i miss because of my poor capacity in using APDL, so i'm asking for some suggestions: are there any specific commands that i have to use? I follow a scheme like:
1. Add materials in element type (solid45 for brass, solid5 for pzt, circu94 for the electric part that i don't need for this first analysis)
2. Choose the material props thar i've found on datasheets
3. Modeling the cantilever (2 volumes one on the other): 4.85x1.0x0.4 mm brass and 4.85x1.0x0.5 mm for pzt
4. Glue the volumes
5. Attribute the materials and mesh the model with mapped mesh (0.5mm per edge)
6. Put the boundary conditions on the blocked area (pzt+brass) UX=0, UY=0 and UZ=0
7. Solve modal analysis
This is the result of the first mode:
I'm so upset! I hope someone could help me!
Thanks!
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Dear scholars,
Suppose we have a vibration-based piezoelectric energy harvester (cantilever beam), the generated voltage is measureable via a multimeter. Questions are:
1- how to measure the harvested power? What type of electric circuit is required?
2- Do we need a rectifier to change the AC current into DC current? (Knowing that the appliance to be charged needs DC current)
3- do we need a battery or a capacitor to store and use the energy?
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Using bridge rectifier and filter, convert to D.C voltage (V) from A.C . Using stander resistance (R)load the D.C voltage and find the flowing maximum current (I). The power could be obtained as W=(V)(I) or (I)(I)R, obtained power by both ways should be same....
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Connect two unimorph piezoelectric beams series and parallel in COMSOL and ANSYS to get voltage output for series and parallel connection.
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Thanks, Premkumar sir for your suggestions. I will try that sir.
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I need to compare the agility of two piezo actuators. I saw a relation between rising time and resonant frequency in the following website: Tmin=1/3f0
According to the formula, an actuator with a higher resonant frequency is more agile.
I need a reference for this formula if it's correct or other relation and reference.
Thank you.
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The rise time and resonance frequency depend on the load applied to the PZT.
The best way to measure the rise time of a PZT is to bond a calibrated FBG on the PZT in the direction of the axis one needs to test. Notice that each axis directib will respond diferently. To monitor the FBG displacement peak do not use a commercial FBG interrogator because they are frequency limited and to neasure a PZT rise time needsa much higher frequency.
To monitor the FBG you can use the twin FBG technique or a manually adjustable Fabry-Perot filter. If you need to know more about these techniques call me at mwerneck@ufrj.br
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Please suggest some good quality and free journal with very short response time for MEMS, piezoelectric energy harvester research?
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Dear Author,
I also suggest MDPI Micromachines for your mean. Regards.
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Hi...
I have create a piezoelectric friction damper in Ansys for seismic protection..now i wamt to add semiactive control algorithm for that damper. How i can do that..if anyone can help me....
Thank you
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Actually i have create piezoelectric friction damper in ansys. I want to add semiactive approach in ansys.
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Like Vortex Bladeless Turbine !
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Wind power is already sparse without adding piezoelectrics, which are very inefficient. Conventional rotating generators are quite efficient and well-suited to wind turbine applications.
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Dear community,
I need to model the current flow read by an amperometer between two aluminum plates with an interposed piezoelectric pzt plate.
The aluminum and pzt are connected via tie constraints.
The upper plate is loaded with a uniform pressure, while the bottom plate is fully constrained.
The pzt displays a potential different upon loading as it should.
The problem is that the structural elements assigned to the aluminum plates don't have the electrical potential nodal d.o.f., but at the same time electrical structural elements cannot be coupled with piezoelectric elements.
Do I need a user defined structural element with an added d.o.f. for electrical potential?
Also, how do I model the amperometer?
Best regards.
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Try this
And more detalisation
This Piezoelectric model is reversible with respect to electrical and mechanical stress.
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Hi all,
Please any help with piezoelectric simulation. I can get (stress amplitude vs frequency) diagram, but how can I get Volt vs frequency diagram
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Do the frequency domain analysis with fixed body load at fixed frequency (generally resonant frequency). This is done by attaching an external load to the pz device using electric circuit module. After define the range of frequencies for which u want to simulate. After completion of simulation, select 1D plot in which selct global plot and use the expression abs(V) and click plot. You will get voltage generated by pz device across external load.
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I am working on piezoelectric energy harvesters that mounted inside vehicle tire to harvest strain energy and power sensors attached inside the tire.
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Dear Ibrahim Al-Najat
COMSOL can solve piezoelectric problems. you can get an idea from this tutorial also:
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Wn affects the load resistance formula (R=1/(Wn*Cs). I am not able to match the graph obtained in this paper, would appreciate some input on this. Thank you.
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I read the paper and I would relate this formula with the mechanical quality factor Q given by:
Q=Wn*R*Cs
In the paper, Cs is the clamp capacitance, for this reason one can obtain R=1/(Wn*Cs), being Cs the clamp capacitance.
I hope that helps
Lucas
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Can the current and voltage generated by the piezoelectric vibratory energy harvester be measured experimentally?In other words, can we measure the power generated by the piezoelectric vibration energy collector ?
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There are two options:
1. (Easier) Measure the voltage of a resistor placed into the piezoelectric eletrical terminals. Then, you have the value of the resistor and the measured voltage. Thus, it is possible to calculate the current by I=V/R.
2. (Harder but more comprehensive) Connect a frequency analyzer equipment into the terminals of the piezoelectric device. Then, it is possible to extract the frequency response (gain as function of frequency). Usually, frequency analyzers can provide voltage gain as function of frequency. You can also use a resistor as load in this case.
I hope this helps
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A most simple energy recovery device, piezoelectric cantilever beam, load resistance, how to use simple equipment to measure and calculate its output power?
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I am working on the design of an auto-adjustable 25khz 2000W ultrasonic generator(power supply).
I will use that to generate the ultrasonic power of a welding system.
"auto-adjustable" means that it can find the right working frequency of the transducer by getting feedback from piezo stacks.
I am looking for books or websites or papers that can help me in my work.
If you have a circuit design designed for this purpose, I would be grateful if you could share it with me.
thanks
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We are going to prepare magnetoelectric porosus scaffolds (metamaterials) and also laminate structures. Please could you share your experiense , which 3D printing approach is the best choice to start working on. In the case of piezoelectric materials we would also like to have any opinions based on your experience.
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First, the raw materials should be prepared in powder form, and then these powders should be layered on top of each other. This method of 3D printing is suitable, and finally, decorates the final material. Of course, you should be sure that you can prepare raw materials in powder form. Preparing raw materials in powder form may be a big challenge for you.
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Research and development of lead-free piezoelectric materials are presently the hottest topics in the field of piezoelectricity. Also a huge advantage of PZT and related systems, is that this one family, with minor modifications, is suitable for nearly all applications.
Environmental and health issues related to Pb-based materials are obvious. According to RoHS, any homogeneous component containing more than 0.1 weight % of lead is subjected to restrictions ; and hence, the fact that the best piezoelectric materials contain lead up to 60 weight %, may in the future, seriously hamper their use in everyday applications.
my question is that "why people looking for replacement for PZT ( lead zirconat titanate ) which contain Pb up to 60% of weight because Pb is considered toxic or dangerous for life . While the alternative lead free piezoelectric KNN, BNT , BNN , BST , BT , BZT , all these alternatives also might contain toxic or hazard element for example Barium is toxic and dangerous for environment "
Why people want to replace lead? The alternative are toxic also? so why the replacement of hazard element with another hazard one ?
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Piezoelectric materials based on lead have held several applications such as automobiles, microphones, sonar, resonators, medical imaging/diagnostics, printers, ultrasonic motors, wearable devices, smart structures, medical implants, etc.) for over 50 years. The dominance of PZT-based ceramics is due to their superior piezoelectric response, which ultimately ensures an unmatched efficiency in the direct interconversion of electrical and mechanical energy. Beyond this superior piezoelectric response, lies a level of toxicity that threatens the position of PZT as the leading piezoelectric ceramic, and has sparked urgent global efforts to identify environmentally benign substitutes. A fundamental issue that emerges with the recognition of lead toxicity is the need to find surrogate materials in the myriad of products in which PZT plays a major functional role. Potassium sodium niobate (K x Na1−x NbO3 or KNN hereafter) is a potential Pb-free replacement for PZT[ 4 ] and for room temperature applications in particular looks promising. Material replacement in existing products has many obstacles, such as substitution costs, price ratio, and in some instance the end user's propensity to change. Consequently, for material substitution to be viable: (i) the benefit of implementing a novel and untested material must be worth the risk of abandoning the well-established current materials; (ii) the cost of substitution must not exceed the overall benefits; (iii) the costs of renovating production equipment and processes is acceptable; (iv) the implications of substitution are manageable in a wider systems context; and (v) institutional, legal, social, and environmental consequences can be overcome.
For more information, you can read this article.
Ibn-Mohammed, T., et al. "Are lead-free piezoelectrics more environmentally friendly?." MRS Communications 7.1 (2017): 1-7.
Regards
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Does this power generated can be stored in batteries? Application could be in shoes and foot paths in order to harvest energy. I'm working on these applications would like to know all the possible options please.
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Hear me out. We build a pyramid lined with quartz crystals in order to use the natural vibrations of the earth to harvest electricity. This is a theory of what the Great Pyramids of Giza were actually for. We know they were lined with quartz and the top was gold which is highly conductive.
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How to do Piezoelectric coupling in ANSYS-APDL or COMSOL between tapered substrate and rectangular piezoelectric patch?
Piezoelectric coupling between the rectangular substrate and rectangular piezoelectric patch is simple. Because the beam and patch are correctly meshed for the same size to coincide the nodes in all directions.
But in the case of tapered beam (non-uniform cross-section), the elements will be irregular after meshing, very difficult to coincide the nodes correctly. So piezoelectric coupling not able to correctly to get voltage output from that.
Suggest your views for this problem.
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Dear Raja,
to solve your issue you have two options,
The first one is by defining a contact between the substrate and the patch (this can affect significantly the computational time ),
The second is by dividing the geometry using VSBW this allows you to have a coincidence nodes
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I am doing buckling analysis of laminated plate surface bounded with two piezoelectric PZT 5H and axial compressive load is applied.
I am getting an error, No ANEL table exists for material 2. (attached buckling.jpg)
I am taking material properties from published literature but no such data available on paper. attached (material.jpg)
please help me with this regard
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Hello Prashant,
In a general sense regardless of the application, to perform nonlinear buckling in ansys you may follow the following steps:
1.Create linear static analysis with a small value of your load for the given boundary conditions.
2. then perform eigenvalue Buckling to get the buckling mode for this configuration.
3. after obtaining the buckling mode shape, the nonlinear analysis under the desire loads can be done with one of these options; a) update the geometry based on the first buckling mode to get imperfection or b) impose a small load or displacement to replicate the buckling mode
Eventually, even though it is a different application, this demonstration could help.
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I have a circular PZT layer deposited by PLD method. The dimensions are: 20um diameter and 350nm thick. It has 100nm Pt electrodes sputtered on the top and bottom. I would like to know what is the maximum voltage it can withstand?
I would assume that the withstanding voltage will increase proportionally with the thickness. Is it correct?
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It is depends on area and size of layer.
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Hello Everyone,
I intend to carry out piezoelectric simulations in ABAQUS. For that I am coupling mechanical and electrical field. But the problem is how to couple electric voltage (EPOT) between upper surface and lower surface. In ANSYS APDL, we have direct couple DOF option enabled which couples the Upper surface nodes and lower surface nodes. But in ABAQUS I found it's quite difficult.
Does anybody working on ABAQUS has any idea to above problem? If anybody has any paper or video, please share.
An early reply is highly appreciated. Please do needful.
Thank You !!!
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No not yet.. For time being I am not working on computational part... However, if you require any help regarding experimentation please let me know...
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I am doing modelling work of piezoelectric sensors bonded on the surface of the host structure. I have been doing this work in ANSYS APDL. I made three geometries for PZT patch, adhesive layer & host structure & using boolean operator, I glued them all. But the moment I mesh the host structure (bottom one), this error appears & consequentially, I am unable to proceed ahead. Please help me out. Any help would be appreciated.
Hex. (brick) meshing is preferrable.
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Divide the base volume into small volumes exactly as the adhesives. Either glue them before meshing. I have added some illustrative lines in your figure so that you can understand it better.
I hope this works.
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I want to design a piezoelectric transducer which would be designated for wireless communication through agricultural water pipes. The frequency has to be under 30 KHz and the diameter is 15 mm.
I found out that piezoelectric buzzers answer those requirements, but I didn't find an existing product that is used for this purpose.
Is it possible to use a piezoelectric buzzer for this purpose? If so, what kind of changes do I have to make to the buzzer in order to match it to meet my requirements.
Thank you in advance!
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Are you interested in sound transmission through water or pipe material?
Which distance is interesting for you?
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I need a Matlab code of the differential quadrature method to solve the equation of motion of a vibrating piezoelectric beam knowing that I used Euler Bernoulli's model ??
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[D]=Diff_Quad(N);
Differential Quadrature Matrix for 1st derivative based on Lobatto grid.It calculates for N grid points.Higher derivatives can be easily calculated by using D matrix.
Or this might work: (as an example)
function [D]=Diff_Quad(N)
%
% Differential quadrature matrix for N
% points based on Lobatto grid points.
% D matrix converts the diff. equation into eigenvalue problem.
% y'=A*y --> Dy=Ay
%
%
% For any questions and critiques
% Altug Bicak @ 2005
for ii=1:N
X(ii)=0.5*(1-cos((ii-1)*pi/(N-1)));
end
SagTaraf=1;
Taraf=0;
for ii=1:N
for jj=1:N
if ii~=jj
a1=(1/(X(jj)-X(ii)));
for k=1:N
if k~=ii & k~=jj
SagTaraf=SagTaraf*(X(ii)-X(k))/(X(jj)-X(k));
end
end
a(ii,jj)=a1*SagTaraf;
SagTaraf=1;
end
if ii==jj
for k=1:N
if k~=ii
Taraf=Taraf+(1/(X(ii)-X(k)));
end
end
a(ii,jj)=Taraf;
Taraf=0;
end
end
end
D=a;
tic
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The goal is to design a low frequency (under 40 KHZ) Piezoelectric transducer. Transducer diameter must be under 16 mm.
The idea I have is an air-coupled flexural transducer with a PZT disc.
I am searching for articles and information for my research in order to choose the correct backing layer material and other components materials.
Thanks in advance for any help.
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Backing materials tend to be a bit experimental. The aim is to make the best possible attenuator and to damp the resonance or not as is desired by your application. Good materials have particles that are sized according to your wavelength so for 40KHz something in the order of 1-2 mm would be good. The particles should be held in a matrix of polymer which has a difference in acoustic impedance. The absorption is a function of the sound entering the particle and passing through against the reflected energy. With this in mind the acoustic impedance should be mismatched but not by much.
16 mm diameter is small for a 40KHz transducer and will have a significant beam spread.
In practical terms crumb rubber held in a PU matrix is a good start. If your limited on how many piezo elements you can afford, start by making cast slugs of various rubber compositions (recording the mix) and see how much sound you can pass through with a liquid coupling from one side of the slug to the other. The slugs can be bonded onto the piezo element but are better cast in-situ.
Addition of metals such as tungsten is used for high frequency, broad band probes. I would think you need a narrow band for air coupled.
https://etheses.bham.ac.uk/id/eprint/1311/1/Webster10PhD.pdf give a good summary of higher frequency construction. has a good selection of links.
In conclusion, a theory driven experimental approach is needed to get a good result.
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