Hysteresis is the dependence of the state of a system on its history. For example, a magnet may have more than one possible magnetic moment in a given magnetic field, depending on how the field changed in the past. Plots of a single component of the moment often form a loop or hysteresis curve, where there are different values of one variable depending on the direction of change of another variable. This history dependence is the basis of memory in a hard disk drive and the remanence that retains a record of the Earth's magnetic field magnitude in the past. Hysteresis occurs in ferromagnetic and ferroelectric materials, as well as in the deformation of rubber bands and shape-memory alloys and many other natural phenomena. In natural systems it is often associated with irreversible thermodynamic change such as phase transitions and with internal friction; and dissipation is a common side effect.
Hysteresis can be found in physics, chemistry, engineering, biology, and economics. It is incorporated in many artificial systems: for example, in thermostats and Schmitt triggers, it prevents unwanted frequent switching.
Hysteresis can be a dynamic lag between an input and an output that disappears if the input is varied more slowly; this is known as rate-dependent hysteresis. However, phenomena such as the magnetic hysteresis loops are mainly rate-independent, which makes a durable memory possible.
Systems with hysteresis are nonlinear, and can be mathematically challenging to model. Some hysteretic models, such as the Preisach model (originally applied to ferromagnetism) and the Bouc–Wen model, attempt to capture general features of hysteresis; and there are also phenomenological models for particular phenomena such as the Jiles–Atherton model for ferromagnetism.
I am currently working on a FE simulation project where a tensile test of DP800 steel is subjected to cyclic loading.
It utilizes Yoshida Uemori model (YUM) to formulate the modulus of elasticity (E) to simulate the hysteresis caused by cyclic loading.
We are using a USDFLD subroutine in...
We recently did an experiment to generate the hysteresis curve of a certain material. The experiment involved switching the current in the wire looped around a ring of the material, and recording the first throw of the ballistic galvanometer. I am not going into the details of calculations...
At the heart of the theory of open quantum systems is the idea that the measurement statistics of many-body systems can be expressed in terms of a reduced density matrix, obtained by tracing over degrees of freedom that are irrelevant to the system of interest.
In general, given a pure state...
Could anyone help me with some info on compression helical springs. First I would like to know if this type of spring would even have any appreciable histeresis when new, and if so does it does it grow with repeted use and age. I would also like to know if there is any relationship beteen the...
Hello,
In reviewing friction, I realized a couple of things: the coefficient of static friction can be larger than 1 (always thought it would be smaller than 1), that the surface area does not matter for static and kinetic friction ONLY for simple solid, rigid objects ( for materials like...
Summary:: My college assignment brief;
Write a report in which you examine and describe the differences in the elastic, magnetic, and electric hysteresis experienced by the steel, polyurethane, and concrete materials respectively.
The scenario:
You work as a mechanical engineering for a marine...
Hi!.. As known, a certain amount of energy is applied for compressing a mechanical spring. Thus mechanical spring is charged with energy and it stores it as elastic-potential energy. But whole energy, applied for compressing spring, can not be converted into potential energy. The reason is...
(Edited with suggestions from Berkeman)
After reading the original 1930 paper by Sawyer and Tower (link to original paper here), I noticed that their hysteresis loops are mirrored around the y-axis from many of the ferroelectric hysteresis loops reported today ( see FE examples here, here...
Hi all, I am working on perovskite solar cell related studies. J-V curve (current density-voltage curve) is one of the important measurements to determine the performance of the device. In practice, we perform the reverse scan first then then followed by the forward scan. There is usually a...
Homework Statement
sorry just started my hnc in engineering and electrical the worst part for me
is this right
a current is applied a magnetic field is generated. current is reversed zeros its repeat. metal maintains degree of magnetizem dipole aligment. the magnetic field lags behind the...
I am trying to simulate an electric motor in ansys maxwell software, but I can't define the whole loop in four quadrants for the material used in the rotor however it is essential to do this since the motor is of hysteresis type and works on the principle of working point moving all around the...
Let's suppose we are given a set of requirements and we are to design a motor that meets them. Requirements are:
3 phase synchronous, 480v, 50Hz and of hysteresis type and alnico is the only available option and it should deliver a 0.6N.m output torque.
Dimensions should not exceed 150 mm and...
Hello,
I'm trying to simulate a 3 phase hysteresis motor with 4 poles, 36 slots, 220 input voltage peak for each phase, 50Hz, specified dimensions and 0.6 N.m output torque in maxwell transient.
The magnetic material used is LNG52 which is also known as alnico600, alnico5DG(ACA52) and alcomax...
Please help in the explanation of BH curve (See attached file).
At the starting point, more current is required to bring the material to its magnetic saturation point( in fig form origin to pt.a shown by purple line ) as compared to when the material is fully demagnetized and then brought to...
Hello,
I am designing a circuit which basically takes two voltages (V1,V2) and based upon which one of the two is greater, turns corresponding LED. So, I have got to the part where I have output from differential op amp that is the input of the inverting voltage comparator with hysteresis...
hello i have a few questions regarding hysteresis loop in ferromagnets as showen here .
i had an experiment in which i took a piece of gadolinium and cooled it down using liquid nitrogen , than i put it in an apparatus as showen here , so i induct an oscillating magnetic field on it , forcing...
In a lab we had to measure the remnant magnetisation of a hysteresis loop with a permalloy core. The amplitude of the input sinusoidal wave was varied and the resulting remnant magnetisation measured. This was then plotted resulting in the remnant magnetisation varying sinusoidal with the input...
I am taking an experimental course which requires us to conduct experiments by ourselves. One of the tasks is to demonstrate the flux pinning effect of a type II superconductor YBCO by magnetic levitation. The professor asked me to discuss the effect by using the hysteresis loop (magnetization...
I'm curious if there is any documented effect along these lines, via EM waves. Hypothetically, all objects have a resonant frequency which will cause them to vibrate when matched. As an example, stone has a resonant frequency per type, its molecules also, atoms also, and I personally theorize...
Hi Guy's, I'm starting a project to explore the physics of hysteresis friction between two surfaces.
One flat metal surface is considered to have zero compressibility but does have grooves interrupting the sliding action.
The second material (organic elastomeric compound) also having a flat...
Hi everyone !
I'm currently working on a project for which I need to measure the advancing contact angle of a liquid on a solid, specifically the advancing contact angle of a molten thermoplastic on carbon fibers.
My understanding is that there is a difference between dynamic contact angles...
Hello,
I have piezoelectric film. I want to characterize ferroectricity. which exact equipment and circuit are used for measuring polarization-electric field hysteresis loop.
Thanks
Hi,
I am trying to use ANSYS workbench to model a steel frame with steel cross bracing (HSS 32*32*3). The post-buckling behaviour should be similar to the Remennikov-Walpole analytical model (1997) where in a rigidly fixed ended brace three plastic hinges will form in buckling. The expected...
I'm working with hysteresis losses in transformers at the moment, and I was wanting to know if there are units for the coefficient.
Normally, I'd just rearrange the equation for units, below,
h=ηB1.6f
η=hf-1B-1.6
so it would have units
JsT-1.6
However, given the power of 1.6, I'm not sure it...
This question is primarily regarding transformers, particularly the impact frequency has on hysteresis loss.
Given hysteresis loss = η×Bmax×f×V
and Bmax = (V ×〖10〗^ 8)/(√2 π×f×N×A)
This means that hysteresis loss
= η (V ×〖10〗^8)/(√2 π×f×N×A) fV
= (η ×〖10〗^8)/(√2 π×N×A) V^2
And as such...
Hi people,
In my college laboratory we were assigned an experiment to measure the hysteresis curves of a certain ferromagnetic material at different temperatures. Sounds simple, right? Well, the block of Monel 400 we chose did something weird.
We cooled it down to about -200°C and set about to...
Hi. My colleagues and I are doing a research on transformers (single-phase) and we stumbled across the following equations involving hysteresis and eddy current losses:
Wh = ηBmaxxfV
where Wh = hysteresis losses
η = Steinmetz hysteresis constant
Bmax = maximum flux density
x = constant...
Let's consider the Magnetic hysteresis loop of a certain material: https://www.nde-ed.org/EducationResources/CommunityCollege/MagParticle/Physics/HysteresisLoop.htm is an example. In many sites and books it is written that its area is proportional to the energy wasted as heat, so A = kE_d.
In...
Over the years I've learned a lot about TXs etc. But I'm a bit rusty. Any thoughts on general reminders about core saturation.
I know there are huge issues, but the specifics I can't remember that well. I vaguely remember hearing something like when there is a DC component on a transformer the...
Hi,
Do helical springs have hysteresis. Say I do an exercise of plotting deformation Vs load curve of a helical spring, one way will be starting from load zero and increasing till the spring achieves solid length. The other way will be loading the spring till solid length and measuring...
Hi all, I was researching into Induction Cooking (using induction plates) recently and chanced upon a few websites that mentioned about hysteresis in Induction Cooking. However I don't really get how does hysteresis have a part to play in Induction Cooking. :/
Hi,
There is a rattling noise in one of the automobile passenger car gearboxes that we designed. After few experiments and observations, it was found that the noise is because of incorrect clutch stiffness and hysteresis behavior. I have got some fundamental questions about both:
1. Clutch...
The question
I've been given this question by a teacher and I'm clueless as to what b) and c) are. Could you please help? I would really appreciate it. The prize is a place to see a lecture on quantum simulation at our local University.
Thank you :)
hi my dear friends
i face with a problem in ansoft maxwell;
i want to import a hysteresis material's loop into maxwell's material s libraray
but i cant!:(
is there anyone who can help me?
with the best wishes:)
pedro
Hello,
I'm having some problem in understanding what is hysteresis. can someone explain it to me what is hysteresis, and how can i make the value big or small as i wish?
Wide/Narrow Hysteresis loops, what's the difference?
When calculating the work done to magnetize a ferromagnetic material, calculating the hysteresis loop is the right way?
I know the narrower loop(soft) needs less energy(work) to magnetize or demagnetize it is that true?
That's why it's...
Hi, I have been reading about magnetic hysteresis and all sources refer to magnetic field strength (H) as having the units (A/m). Why is it just amps/meter and not ampere-turns/metre as H = NI/L and not N/L? Is there another equation for H that I am unaware of?
Cheers.
Stretch piece of metal within its elastic limit and it cools down.
Does it cool down for the same reason that a gas cools down when expanded?
But if the piece of metal is repeatedly stretched and released (like with a spring), I am led to believe that it heats up, although I am not sure.
I know...
As fare as I have researched UVLO Under Low Voltage Lockout is a circuit which is used to turn off and on the output power of a electronic device according to voltage selected. For instance in a charging circuit the power will only flow to the load once the capacitor has charged to a certain...
Hi all,
I want to measure electric polarization hysteresis loop so i need the electric circuit to measure it.
The circuit mostly contains a resistor and a capacitance, i need to what is the exact value of them ?
Please tell me if there is a reference for that
Thank you
I wish to know why and how does hysteresis occur from a purely mathematical perspective, using analytical functions and multivariable calculus. Thank you!
Hello, I am new to the forums and physics in general. I hope I am not posting in the wrong place. My understanding of physics in general is rudimentary at best, so please let me know if any of my statements are incorrect.
I understand this is an extremely long post, so feel free to jump to...
Alright so I have been given a table for a transducer as follows:
Operation
Input range 0–1000 cm H2O
Excitation 15 V DC
Output range 0–5 V
Performance
Linearity error 0.5% FSO
Hysteresis error Less than 0.15% FSO
Sensitivity error 0.25% of reading
Thermal sensitivity error...
Homework Statement
Consider an inductor, with a core of ferromagnetic material, connected to an a.c. power supply. Explain why the contribution of the hysteresis losses to the resistance of the coil is theoretically proportional to the frequency of the oscillator.
The Attempt at a...
Homework Statement
What hysteresis loop shape would you require for a magnetic material to be used in
A) a permanent magnet
B) transformer core
The Attempt at a Solution
No idea what this means...but it is for my lab tomorrow so I probably should.
Any help would be greatly...
I am trying to show that there are 3 nonzero steady states of
\frac{du}{dt}=ru\left(1-\frac{u}{q}\right)-\left(1-\exp\left(-\frac{u^2}{\varepsilon}\right)\right)=0
I have tried using Mathematica and Mathematica couldn't solve it.
I tried some algebra and that wasn't going anywhere so I am at a...