Questions tagged [piezoelectric]
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What if we apply a torque to a piezoelectric plate?
Consider a circular thick plate made of piezoelectric material kept horizontally inside a viscous medium. If we apply an upward force on one side of the plate and downward force on another side of it, ...
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Why would the dielectric constant at zero strain be different than the dielectric constant at zero stress?
Hello. My question is about the last equation, where the conversion is between dielectric constant at zero strain and the dielectric constant at zero stress. What's the difference between them? Why ...
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How to write the dot product of 3rd order tensor (piezoelectric constant) with 1st order tensor (Electric field vector) in the matrix form?
In the Stress-Charge form of Piezoelectric constitutive equations:
$T$ $=$ $c$ : $S$ $-$ $(e^T) . E$
( The symbols are explained in the picture below)
My question is, why do we take the transpose of $...
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I want to know the relationship between the frequency applied to the piezoelectric vibrator and the exit frequency
We purchased a vibrator with frequency characteristics including the desired frequency. Now, to produce a sound with a single frequency, it is difficult to know how to determine the frequency of the ...
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How would one calculate the electric field produced by a piezoelectric device in response to a sound wave?
So the governing equations of piezoelectricity are:
Where E is the electric field, D is the displacement field, S is the strain, and T is the stress. Say I have a piezoelectric device where the ...
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Crystals and charge
I've been researching on Piezoelectric crystals. And i've been wondering that could keeping constant pressure on piezoelectric crystals create a constant flow of electricity?
I've tried googling it ...
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The change of mechanical into electromagnetic waves and vice versa [closed]
I know that sound is a type of mechanical wave, so the human eardrum changes mechanical energy into electronic energy (impulses) so the information may be processed by the brain.
Question: As ...
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Is the direction of sound from a piezoelectric independent of the polarity of the voltage?
My understanding is that if a patch of piezoelectric is electrified, sound pressure is emitted from both electrified sides:
If so, then isn't the emitted sound essentially the same if it's supplied ...
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How does current behave in a piezoelectric circuit?
I am trying to understand the fundamental principles of piezoelectrics, but my searches haven't helped me answer this question. As I understand it, squeezing a piezoelectric causes a mechanical ...
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Quartz crystal resonance frequency simulation
Is there an open source/scientific software package that would allow to simulate Quartz crystal resonance frequency for specific cut angle, crystal geometry and temperature? How would one approach ...
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Transverse and Longitudinal waves
I am performing an experiment where a steel ball of diameter 7.5 mm is dropped by hand on an aluminised kapton foil. Four piezoelectric sensors are placed 55 mm away from the edges at a 45 degree ...
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Piezoelectric equations
I've seen two sets of equations for Piezoelectric(and converse piezoelectric) effect in different references,
first set which is introduced in "Elements of Group Theory" by A.W. Joshi are:
$$...
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Why is a phase shift through a time delay not used for damping in vibration dampers?
Why do oscillation dampers use signal conversion through a sufficiently massive electrical circuit (with resistors, capacitors, diodes) to create antiphase, instead of simply shifting the signal in ...
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Lowering pitch of a piezoelectric buzzer
I have tried to drastically lower the pitch of a piezoelectric buzzer, but to no avail. All the piezo buzzers I have emit a very high pitched whistle-like tone. I've tried changing all the parameters ...
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I will like to know how to measure displacement using a piezooectric transducer
I am attaching a piezoelectric patch at a point of a moving object, I will like help to know how to convert the output voltage responseI get drom an oscilloscope to displacement values in mm.
I will ...
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What are typical resonant frequency ranges of large crystals?
I want to measure the resonant frequency of a crystal about 1 inch long using a transducer and a contact mic. What frequency ranges should I select to be able to measure a variety of different ...
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How does a piezoelectric oscillating cantilever fan operate in different gases?
A piezoelectric oscillating cantilever is a structure composed of a piezoelectric material with a flexible blade attached to it. While alternating voltage is applied over the material, it starts ...
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Energy Utilization in Electromagnetic Actuator Vs Piezo-electric Actuator
Electromagnetic actuators are quite common in almost all industrial and household applicatons. I was wondering that the motion produced by the electromagnetic actuators are the side product of the ...
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What is a piezoelectric sorption detector?
I'd like to know what a piezoelectric sorption detector is. I can hardly find information about, only a small number of research papers which are mostly not accessable for me.
Only given from the term ...
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Capacitance of ferroelectric capacitor in saturated regime
Consider a ferroelectric plate capacitor connected to an AC source in the presence of a strong static external electric field which sets the ferroelectric medium in the saturated regime.
The question:
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Why all ferro-electric materials are also pyro-electrics?
Ferro-electricity is the property of some dielectric materials to keep a net residual polarization even after the electric field is removed. They tipically present a hysteresis cycle doing this.
It ...
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Lagrangian of a piezoelectric material
I am confused about the Lagrangian of a piezoelectric material. I have seen multiple sources that seem to contradict each other.
The way I personally approach the problem is the following:
$$L = K - ...
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Why does "AT cut" of Quartz provide pure shear thickness oscillation?
According to this page https://www.nanoscience.com/techniques/quartz-crystal-microbalance/,
“AT cut” provides pure thickness shear mode oscillation where the two surfaces of the crystal move in ...
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How to increase the frequency of a water wave?
I am working on a piezoelectric device in a sea wall. Piezoelectrics take mechanical loading (like being squeezed) and can output an electrical signal. Unfortunately piezoelectric's don't work well in ...
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Why are piezoelectric transducers coated with electrodes on top and bottom? [closed]
I am learning about piezoelectric transducers and I want to know why the piezoelectric material is coated with electrodes in top and bottom ?
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What does it mean by (±20%) in sensitivity of a pressure sensor?
Sensitivity: (±20%) 15.5 pC/psi (225 pC/bar)
this the sensitivity rating of a pressure sensor.
what does it mean by (±20%).
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Resonance frequency and impedance of a piezoelectric element
I am reading about piezoelectric elements, and I have some questions in that regard. I have come across a graph showing the impedance as a function of frequency. Some spikes occurs on the graph at ...
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Why is a piezoelectric material a capacitor?
I am reading about piezoelectric elements and I am not sure why a piezoelectric material is like a capacitor. So a mechanical stres on the material will displace the electric charge distribution ...
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How to determine resonance frequency of a piezoceramic element?
Lets say we have a circular piezoelectric element with radius R and height H. We assume that the piezoelectric element has density $\rho$. How do you find the resonance frequency ? Is there a formula ...
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What is the difference between a Surface Acoustic Wave (SAW) (Rayleigh Wave) and a Leaky SAW?
I have come across leaky SAWs and I'm not sure what the difference is, and why some substrate cuts are listed as leaky SAW design.
Trying to search for diagrams so I could see what the differences ...
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Piezoelectric effect and area
I would like to know if my reasoning is correct for this situation, as I am unsure.
I have two piezoelectric substrates, on both of them I deposit an active film on one side of each, that will change ...
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Is there an electric field in a poled piezoelectric crystal at rest?
From my understanding, after a piezoelectric crystal is poled, all the dipoles are roughly aligned inside it, so that the piezoelectric effect is not negligible. However, wouldn't that result in a ...
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What makes quartz oscillators vibrate?
I understand that the principle behind it is piezoelectricity and electrostriction (inverse piezoelectricity), but how does one make the crystal vibrate?
The only thing I can think of is using an ...
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Piezoelectric strain curves and magnetostrictive strain curves
I am trying to understand the differences in the strains produced in piezoelectric materials and magnetostrictive materials.
Magnetostrictive materials will tend to strain the same way along the ...
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Perpetual Motion Machine 1: Magnetic Superconductor Loop Generating Energy with Piezoelectrics [closed]
I know there are a lot of perpetual motion machine designs out there, but I haven't found one that looks like this one. I will use this diagram.
Assume the entire ring is made of a superconducting "...
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Energy can be created
Consider a device which converts kinetic energy into electrical energy ( just like piezoelectric generator). Now I install this on two trains of very high mass approaching each other (moving in ...
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How are the orientations and cuts of crystal substrates determined?
I have been looking at piezoelectric crystals, LiNbO3 primarily, so piezoelectric devices. But I have had trouble understanding the cuts and orientations that are referred to with the rotated cuts.
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Is there a way to attach a mirror to a piezoelectric?
I want to use a mirror on the piezoelectric in Mickelson setup, how should I connect this?
Resonance frequency of piezoelectric is important for me. Is there a method to not change the frequency?
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Anti resonance frequency of piezoelectric
There is a method to measure anti resonance frequency of piezoelectric? The RC circuit and this relation and equations can measure resonance frequency.
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Why Shifting peaks in impedance-frequency graph with changing the amplitude of input frequency?
we used a RC circuit for measuring resonance frequency of a piezoelectric. And each time, we changed the frequency domain of the input. The impedance model, in terms of frequency, indicates that the ...
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Suggest the method to that the piezoelectric resonance frequency does not change after attachment a piece?
When the piezoelectric is connected to a element such as mirror to use in interferometer, the resonant frequency decreases, we want to use the piezoelectric and mirror on which we can use it, how can ...
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How to estimate energy of piezo igniter discharge?
Question for fun. We all know piezo igniters, these small friends, like following one:
All of them are probably quite similar: same spring, same piezo, same hit force, and so on.
Also I have some ...
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Why do electric moments in piezoelectric crystals have a random distribution of orientations to begin with?
Above is just one picture used to visualize the piezoelectric effect. The explanation usually is that as an electric field is applied to the material, the electric moments of the molecules in the ...
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Piezoelectricity and conservation of energy
This is how I understand piezoelectricity: The molecules of a material have electric dipole moments. When a sample of the material is under mechanical stress, the molecules "slide"/"turn" and become ...
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Piezoelectric powder solution to measure extremely high pressure
Idea - While reading about piezoelectric materials, I thought about mixing piezoelectric powder with silicon oil to measure extremely high pressures (of up to 4000bar).
Experiment - Consider a ...
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PiezoActuator energy loss in a fluidic environment
I am trying to model the loss of a Piezo actuator in a fluidic environment.
A Piezo actuator can be modeled using a Equivalent Circuit model stated below.
http://www.noliac.com/typo3temp/GB/...
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Piezoelctric Ceramic Transducing Capabilties
Piezoelectric ceramics are able to work as transducers, outputting electrical energy when mechanical stress is inputted. However, most ceramics have high static voltage and low current and power ...
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What does the term "inversion symmetric" mean?
I've read the responses to the question `"Lack of inversion symmetry" in crystal?' but I'm still unsure about the meaning of inversion symmetry. Which of the following two dimensional ...
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Difference between Piezoelectric effect and Faraday's law of induction?
I was researching how the transducer works for an ultrasound machine.What I learned was from a piezocrystal (quartz) the applied mechanical stress can produce an alternating electric field (from the ...
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Do piezo materials change volume?
I know that piezoelectric materials change shape when voltage is applied to them,but do they also change volume? Do they keep same volume and just change their geometrical shape,or do they also ...