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Author Topic: FEMM shows interesting OU effect, the airgap is everything.  (Read 19188 times)
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img  Smudge
Re: FEMM shows interesting OU effect, the airgap is everything. « Reply #50 on: 2024-03-19, 11:52:50 »

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Broli,

KJ Magnetics manufacture NdFeB circular arc segments that can be put together to form a ring where the field is virtually fully confined within the ring, see FEMM result in the image below.  I have played with these and you need great care in building up the ring because of the huge attractive forces involved.  So you can create your ring magnet experiment.

Smudge
   
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Re: FEMM shows interesting OU effect, the airgap is everything. « Reply #51 on: 2024-03-19, 15:14:33 »
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Quote from: Smudge on 2024-03-19, 11:52:50
Broli,

KJ Magnetics manufacture NdFeB circular arc segments that can be put together to form a ring where the field is virtually fully confined within the ring, see FEMM result in the image below.  I have played with these and you need great care in building up the ring because of the huge attractive forces involved.  So you can create your ring magnet experiment.

Smudge

Thanks for the suggestion Smudge, I was thinking about doing something similar with very flat cylindric magnets and orientating them in a circular path but this seems less of a pain in the ass.

I am still not too sure how the coercive strength of different PM materials could affect the potential experimental result. I would assume you dont want something that is too hard of a PM for it to not reorientate much of any domains and not too soft so the domains can still "spring back" due to their neighboring aligned domains.
   
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Re: FEMM shows interesting OU effect, the airgap is everything. « Reply #52 on: 2024-03-20, 11:50:20 »
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Here is another illustration I did and an analogy on the previous one in the long document I attached previously. To kind of also illustrate what happens inside of the core. All the forces and torques make more sense if you view it this way rather than the concept of imaginary fields. In fact I believe we could even physically SEE this gyromagnetic effect in action by using thin disc/square magnets on a wheel and attaching to bearings so they can swivel as seen in the attached illustration.

The "rotor" magnet would be in a perpetually torqued state due to the continuous angular momentum change it causes on the flat magnets (domains in a core). This continuous and perpetual imbalance causing a net angular momentum change over every angle causes a unidirectional torque. If the rotor magnet were a coil it would see a change in field and react to this by reducing its "current" which would be an energy loss as we know. But this does not happen due to the permanent spin of the electron, and THAT is where the energy comes from.

Would be interesting to see if such setup would impart enough angular momentum as the gyromagnetic effect is rather small. However recently we have seen that this is not always the case and that we can see this effect even on the macroscopic scale:

https://www.youtube.com/watch?v=oijGMLErqck

I believe the "relaxing" phase might also be important because you need a continuous change occurring.

PS: The force vectors shown is NOT what causes the proposed effect. These are merely the electromagnetic forces at play, these are conservative and dont cause energy changes, however the gyromagnetic effect is there too and THAT combined with the nature of spin linked to the crystal lattice mechanical momentum is what I propose. The magnet array just helps to align the misaligned magnets back and reset the whole system essentially for free which in a purely mechanical gyroscopic system would be almost impossible to emulate without major losses. From keeping your gyroscopes spinning with motors, to perhaps a hydraulic system for the spring back effect to using a conservative force like electrostatics to the direction flipping? Electromagnetism and Gyromagnetic ratio essentially eliminate all of this complexicity for us and we end up with little system losses, in order to maximize the true energy source by torquing down the spin of the very electron.
   
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Re: FEMM shows interesting OU effect, the airgap is everything. « Reply #53 on: 2026-07-16, 16:48:26 »
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Recently I have been going back to the work done in this thread. More importantly the OU claim by FEMM data and also pointed out by smudge here:
https://www.overunityresearch.com/index.php?topic=4594.msg110807#msg110807

However after digging deeper I want to clear the record. As this anomaly was caused by using an incorrect current sign. You could say at the time I was too dumb to understand that this was crucial to the overall balance. As this lead to a portion of the electrical work contribution to be negative (energy gain) rather than positive (energy lost). After correcting that, the COP drops to essentially one across the whole range as can be seen in the attached images. However this gave rise to another OU artifact at low currents this time. However after running simulations at smaller current and distance increments this artifact was also flushed out. So this essentially means there is no OU in the system.

The reason why I went back to this is because first of all I wanted to be really sure about the results and second I believe there still might be way to produce excess energy by leveraging core saturation. However I believe there is only a very specific window where a few conditions need to line up properly otherwise it might end up being so small that it essentially falls below the noise in the data. I believe if you combine a specific BH curve with a specific strength of the magnet and geometry of the coil you can maximize this excess energy significant enough to show up in the data. At least the FEMM validations so far are encouraging as they show FEMM can validate these mechanical vs energy exchanges quite accurately and zoom in on anomalies if needed. However we need excess energy the range of at least 10% to be confident of something interesting going on.

« Last Edit: 2026-07-17, 00:02:55 by broli »
   
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Re: FEMM shows interesting OU effect, the airgap is everything. « Reply #54 on: 2026-07-16, 23:53:11 »
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I made a simple idealized BH curve to further study this and it seems you can achieve excess energy across a full cycle. Of course I might have slipped up somewhere as it felt like walking a mine field but if anyone can point out a mistake happy to look into it.

Attached is the energy book keeping for one full cycle using the different areas of the BH curve. It was not easy figuring this out because during operation the BH curve essentially moves around.

The BH curve can be found here if you want to validate it it yourself
https://cad.onshape.com/documents/ace0a70136def5c66634755d/w/96e2b40b2e89426c173a6b7d/e/b62559c0fb5200307010e3a4?renderMode=0&uiState=6a595e4f2b20a37e38cc3f53

Essentially the core and a coil with a very high current can double the mechanical work. Because the magnet essentially feels double the current that is flowing in the coil because of the core if the coil has a high current equaling the cores surface currents due to its aligned electrons. But you only pay an electrical penalty at the source for the coil not the core. Next step is to validate this in FEMM.
   
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Re: FEMM shows interesting OU effect, the airgap is everything. « Reply #55 on: 2026-07-18, 08:43:22 »

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Your summation has some additional terms that shouldn't be there.  There are seven different areas of the BH curve that you add or subtract, but you sum 12 values!!! When you restrict yourself to the seven values you get a net deliverance of energy from the current source of 14 units of energy that FEMM will equate to the work done by the moving magnet being attracted then pushed away.

Smudge
   
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Re: FEMM shows interesting OU effect, the airgap is everything. « Reply #56 on: 2026-07-18, 11:13:22 »
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Quote from: Smudge on 2026-07-18, 08:43:22
Your summation has some additional terms that shouldn't be there.  There are seven different areas of the BH curve that you add or subtract, but you sum 12 values!!! When you restrict yourself to the seven values you get a net deliverance of energy from the current source of 14 units of energy that FEMM will equate to the work done by the moving magnet being attracted then pushed away.

Smudge

Hi Smudge thanks for jumping in.

And I think you meant 11 not 12 if so then yes you are right because 4 of those 11 values I consider to be mechanical work. Why is that? Well the logic is as follows. When we power up the core with the coil, besides its negligibly small saturation current, we go so far up with the current to essentially double the saturated core flux by using it as pure air coil which means we need to drive the coil current to VERY high levels to about match the fictional surface current of the already saturated core. This can be 10000's of amperes for iron for instance. Now our magnet that is going to be attracted to this will essentially feel the coils very high current and an additionally matching current due to all the core's aligned electrons contributing to its fictional surface current. And that is the real key here. Without the core the mechanical work would indeed have a 1:1 ratio with the electrical source that is maintaining the constant current of the coil. By adding the core however the electrical source still needs to provide the same amount of energy to maintain the coil current but mechanically we about doubled the work because the magnet sees 2 nearly equal strong currents now versus the singular high current if there were no core. Again electrically the flux change is the same for the coil with or without the core as the core is pushed way beyond saturation so the only flux change it sees is due to the magnet approaching which is the same regardless of the presence of the core. And that is how we gain an additional 1 unit of work during the mechanical cycle.

FEMM calculates forces based on field strength and since both the core and coil contribute to this field that would be as if the magnet sees not one but two coils so I am confident that the force will also increase by nearly double as much leading to double the mechanical work than if only the coil were there.

Now I know this is just an idealized example and I believe you wont get an exact equivalent extra mechanical work from a saturated core but I would bet it would be pretty darn close if we tried to match the coil and core's "surface" current, saturation levels and the strength of the magnet.
« Last Edit: 2026-07-19, 06:39:50 by broli »
   
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Re: FEMM shows interesting OU effect, the airgap is everything. « Reply #57 on: 2026-07-19, 08:29:09 »

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Quote from: broli on 2026-07-18, 11:13:22
Hi Smudge thanks for jumping in.

And I think you meant 11 not 12

Yes 11 not 12, my mistake.
Quote
if so then yes you are right because 4 of those 11 values I consider to be mechanical work.
But you have double accounted on the basis that the core creates a force value on the magnet and the coil also creates the same force value, so double the force and double the energy.  IMO that is wrong an I would bet my life savings that FEMMM will show it.

Smudge 
   
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Re: FEMM shows interesting OU effect, the airgap is everything. « Reply #58 on: 2026-07-19, 09:21:14 »
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Quote from: Smudge on 2026-07-19, 08:29:09
Yes 11 not 12, my mistake.But you have double accounted on the basis that the core creates a force value on the magnet and the coil also creates the same force value, so double the force and double the energy.  IMO that is wrong an I would bet my life savings that FEMMM will show it.

Smudge

Well exactly double would a bit too hopeful indeed. But here is a quick simulation run using axis symmetric for a simple coil+core and magnet setup:

core+coil:0A
z-component: -43.657 N

coil:5000A
z-component: -79.0977 N N
core+coil:5000A
z-component: -152.257 N

coil:10000A
z-component: -158.845 N
core+coil:10000A
z-component: -261.043 N

coil:50000A
z-component: -803.702 N
core+coil 50000A
z-component: -1113.47 N

coil:100000A
z-component: -1626.98 N
core+coil 100000A
z-component: -2085.26 N

What this shows is that there is a clear trend in that the core is providing quite a signifcant boost. However if the current goes too high the coil will dominate mostly and you get diminishing returns. So somewhere in that broad current range there is a point where you get the most bang for your buck so to speak. But I would say that 5000A is already quite a good candidate for being nearly double. I have no use for your life savings though :)
« Last Edit: 2026-07-19, 18:54:03 by broli »
   
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Re: FEMM shows interesting OU effect, the airgap is everything. « Reply #59 on: 2026-07-19, 10:39:14 »

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I can see where you find more bang per buck with the coil+core compared to only the coil.  But you have not provided the input energy (bucks) for your more bangs which FEMM + some calculations will give you.

Smudge
   
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Re: FEMM shows interesting OU effect, the airgap is everything. « Reply #60 on: 2026-07-19, 11:41:18 »
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Quote from: Smudge on 2026-07-19, 10:39:14
I can see where you find more bang per buck with the coil+core compared to only the coil.  But you have not provided the input energy (bucks) for your more bangs which FEMM + some calculations will give you.

Smudge

Yes that will require a more complex position sweep analysis which is being worked on.
   
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Re: FEMM shows interesting OU effect, the airgap is everything. « Reply #61 on: 2026-07-21, 16:56:18 »
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It's funny how things sometimes go. I dropped the mechanical aspect of this problem and essentially arrived at the most core representation of this idea. Instead of using a magnet to modulate the permeability of the core. We could reduce the problem to two problems that interact with each other. Essentially a toroidal current combined with a circular coaxial current. When you combine both without a core they would operate completely independent of each other as they would never couple to each other. However when you introduce a non linear medium between them they can interact. Now the two worlds affect each other around the saturation point of the core.

The good news is that this heavily simplifies the problem and gets rids of all kind of issue like dealing with the very strong demagnetization field which led to using extremely high currents. Because the field is completely bound now the currents can stay at a moderate strength to reach the saturation point. The bad news is that this no longer a purely 2d problem which FEMM can solve. However on the plus side it's more of a 2.5d problem. Meaning a 3d solver only needs to solve a tiny slice of this substantially reducing computation times. In fact you can reduce the problem to a slice of the azimuthal section and even a half slice of the cross section of it.

The theory goes as follow:
• Energize the toroidal coil to saturation of the core then keep the current constant
• Increase the current of the coaxial loop
• Because this reduces the flux of the toroidal coil it will induce an EMF
• Now deenergize both simultaneously back down

So where is the excess energy? Well the induced EMF is energy gained first of all. And the last part where both currents are reduced simultaneously means that the coaxial loop returns all energy it was given because from its perspective its flux did not change to warrant a changed energy state. That only leaves us with the initial energy given and final energy obtained from the toroidal coil. The argument is that this dropped energy + energy gained while the current was kept constant is more than the initial energy it was given. Essentially the area for one drops as the base of the triangle drops while at the same time we gain energy not as a triangular area but a rectangular in our B-H curve or in other words you gain twice the energy drop from maintaining the constant current.

Anyway who has Ansys Maxwell laying around to give this a shot?
« Last Edit: 2026-07-22, 05:40:36 by broli »
   
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Re: FEMM shows interesting OU effect, the airgap is everything. « Reply #62 on: 2026-07-24, 10:26:25 »
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AI assisted me with writing a script to better visualize the field inside of this configuration. It shows the behaviour of the field when you switch between the common toroidal current and the coaxial current. At their half mark their sum produces these very cool helical fields around the toroid. It's almso very similar or almost identical to the fields generated in a tokamak reactor as essentially the same coil setup is applied. But of course that is also where the similarities end as the idea here is to use these fields and couple them using a non-linear core rather than generate fusion.

https://www.youtube.com/watch?v=wu6n5A8OQNc

https://cdn.imgchest.com/files/b7546743d1e3.png
FEMM shows interesting OU effect, the airgap is everything.
   
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Re: FEMM shows interesting OU effect, the airgap is everything. « Reply #63 on: 2026-07-24, 10:51:19 »

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Quote from: broli on 2026-07-21, 16:56:18
The bad news is that this no longer a purely 2d problem which FEMM can solve. However on the plus side it's more of a 2.5d problem.
FEMM has this axisymmetric mode that allows quasi-3D simulations.
   
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Re: FEMM shows interesting OU effect, the airgap is everything. « Reply #64 on: 2026-07-24, 13:23:27 »
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Quote from: Verpies on 2026-07-24, 10:51:19
FEMM has this axisymmetric mode that allows quasi-3D simulations.

Sadly it only allows you to simulate the coaxial currents which would be modeled as current going in and out of the screen in FEMM. However this configuration also requires you to define currents that would essentially be circular on the screen. See attached, FEMM's axis symmetry can not model the green circular current which would make up the toroidal winding. This is why I refer to this as a 2.5D problem as a 3d solver would only need to model a single infinitesimal slice of it.
   
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Re: FEMM shows interesting OU effect, the airgap is everything. « Reply #65 on: 2026-07-24, 16:58:50 »
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I perhaps need to revise my previous statement. After doing some theoretical work which is essentially nothing more than simple Pythagorean trigonometric identity. The maximum "COP" of this system is projected to be exactly square root of 2 or 1.4. This happens when both fields twist the domains 45 degrees.

The previous description of the process led to exactly unity. However there is one path which does not.

1) You energize one coil
2) While maintaining a constant current on it you bring the other coil to the same current
3) Then you deenergize both coils simultaneously back down

What that does is rotate the saturate domains by 45 degrees and reduce the flux linkage of the constant current coil.

The math says the energy you get and need to provide for that stage are exactly equal. However what is not equal is the difference between the input energy of step 1 and and the output of 2 coils in step 3. The math says that is exactly sqrt(2) more energy which has to do with the sin and cos of 45 degrees.
   
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Re: FEMM shows interesting OU effect, the airgap is everything. « Reply #66 on: 2026-07-24, 18:25:33 »

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Quote from: broli on 2026-07-24, 16:58:50
2) While maintaining a constant current on it you bring the other coil to the same current
Won't this rotate the ferrite's magnetization vector because of H vector addition of the contributions from the two windings ?
   
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Re: FEMM shows interesting OU effect, the airgap is everything. « Reply #67 on: 2026-07-24, 19:31:00 »
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Quote from: Verpies on 2026-07-24, 18:25:33
Won't this rotate the ferrite's magnetization vector because of H vector addition of the contributions from the two windings ?

Yes that is the point. There is a very simple trigonometric relation of angle and flux change that competes with the linear part of the energy extraction.

I am currently extracting data from the previous FEMM sim I shared. However this might be the worst case scenario for this configuration because the setup nearly behaves like an air core regardless of high of a relative permeability you chose for the core. Unlike a core that has its field fully contained and saturates at low currents this needs very high currents to reach that point potentially drowning out the energy surplus.

Attached you see this. The blue curve is the current v. flux graph when you energize a single coil. The saturation happens around 100KA which is quite high. This does not depend on the core chosen but due to its own high demagnetization field because the field is not contained.

However what is very encouraging in the preliminary data I have gathered so far is that there appears to be a COP bump around the point where we should expect one aka the saturation point. At around 100kA there is a bump in the COP!

Skeptics might say that a COP of 1.00000189 is barely worth noting and they might be right. However I have three arguments against that. First this data says something interesting is happening around 100KA for some reason the total energy ratio is not stable around the saturation point. Is that a mere coincidence when the theory in ideal conditions says it should be around that same point? Second arguably the most accurate value FEMM produces is the flux linkage. Unlike force calculation that heavily relies on a stress tensor mask and thus the underlying mesh discretization, flux linkage is an incredible stable value that converges very quickly on even coarse meshes. So any fluctuation in energy from using this value is highly noteworthy for a solid state system like this. And the third and final point, the maximum energy surplus is a fixed constant amount that peaks only around the saturation point. If you stay below saturation you will never see it if you go too far beyond it  you might end up losing it in the noise of those high energy levels. This might explain why this open core is essentially the worst case scenario as the window to find the current that gives the highest possible COP is very small.

So the logical next step is to hunt for the exact current value that gives us the highest COP peak. The current data uses very coarse current steps but it already hints at us to look around 100kA which is exactly where we expect to find any surplus.  This search can take many days but hopefully it can provide an exact current value at which the most magic happens to motivate further investigation.
   
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Re: FEMM shows interesting OU effect, the airgap is everything. « Reply #68 on: 2026-07-24, 20:49:50 »
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I just realized something. FEMM gives me the freedom to just surround the coil + core with the same non-linear material to contain the field as much as possible.

The preliminary data shows this reduces the saturation current by A lot! So much so I need to rerun the whole thing with smaller current steps at a lower maximum range. But what is very exciting is that this also increases the amount of flux drop by a lot. The theory predicts this should be around a max of 30% or 1/3 because 1-sin(45)= 0.3 in best case scenario. The current graph attached shows its in the ball park of this figure now opposed to previous weak flux drop. Very curious what the full energy analysis will show now.

   
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Re: FEMM shows interesting OU effect, the airgap is everything. « Reply #69 on: 2026-07-24, 21:56:43 »

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Quote from: broli on 2026-07-21, 16:56:18
...the coaxial loop returns all energy it was given because from its perspective its flux did not change to warrant a changed energy state.
Please elaborate about this lack of change of flux.

Quote from: broli on 2026-07-24, 19:31:00
Skeptics might say that a COP of 1.00000189 is barely worth noting ...
Only if this is a numerical precision artifact of the simulation.

Also, please settle your directional terminology for me - IMO: In the illustration below:
1) the current flows in the "toroidal" direction when flowing in the green winding
2) the current flows in the "coaxial" direction when flowing in the one-turn thin yellow ring.
3) the current flows in the "? ? ?" direction when flowing in the yellow shell.

Confirm, deny, correct, amend....



I wish you had made the ring and shell different colors for clarity.  What CAD was this drawn in, anyway ?
   
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Re: FEMM shows interesting OU effect, the airgap is everything. « Reply #70 on: 2026-07-24, 23:04:14 »
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Quote from: Verpies on 2026-07-24, 21:56:43
Please elaborate about this lack of change of flux.
Only if this is a numerical precision artifact of the simulation.

Also, please settle your directional terminology for me - IMO: In the illustration below:
1) the current flows in the "toroidal" direction when flowing in the green winding
2) the current flows in the "coaxial" direction when flowing in the one-turn thin yellow ring.
3) the current flows in the "? ? ?" direction when flowing in the yellow shell.

Confirm, deny, correct, amend....



I wish you had made the ring and shell different colors for clarity.  What CAD was this drawn in, anyway ?

"Please elaborate about this lack of change of flux."

You can ignore the procedure given in that post. After doing the math it led to perfect unity during the entire process. However the current process does not. Again repeating to make it clear what is happening:

1)Bring core to saturation with one coil
2)Now keep that current constant while you bring the other coil up to the same max current. Both coils oppose each other 90 degrees, that is why in air they would not interact at all but with a core that is non linear they do couple. This causes the flux to drop in the first coil because of the non linear core. Essentially you are rotating the saturated domains by 45 degrees. Say the flux had a value of 1Wb at saturation when the domains rotate 45 degrees it can drop to as much as sin(45) or to about 0.7Wb. Its simple trigonometric identity.
3)Now both coils essentially have the same current and flux going through them. Finally bring both coils down simultaneously and recapture their energy.

In ideal cases the theory says step two is complete unity and all that remains is the balance between the input of step 1 for one coil and the output you get back from the sum of 2 coils at a slightly lower flux aka that 0.7Wb. So say input 1A*1Wb/2=0.5J vs 2*(1A*0.7Wb/2)=0.7J or a max cop of 0.7/0.5=1.41 or sqrt(2) to be exact.

Quote
Also, please settle your directional terminology for me - IMO: In the illustration below:
1) the current flows in the "toroidal" direction when flowing in the green winding
2) the current flows in the "coaxial" direction when flowing in the one-turn thin yellow ring.
3) the current flows in the "? ? ?" direction when flowing in the yellow shell.

1)yes
2) see attached
3) see attached

essentially the inner wire and outer sheet are one and the same coil and act just like a coaxial cable where current flows in opposite direction with respect to each other. One of them might not be necessary but having both of them present compliments the toroidal field nicely as the coaxial coil would generate a circular field that would be completely contained in the core just like the toroidal coils fully contained field. That would be the most ideal condition. That is why you need to use trickery in FEMM to truly simulate this. A setup with said currents would be the perfect configuration for this. Because the toroidal coil and coaxial coil generate a field which is 90 degrees from each other. You saturate the core with one coil and then use the other coil to rotate the saturated domains 45 degrees and finally capture the energy of both. The data I am sharing is going over that cycle using the current v. flux graph to calculate energy input/output of each step.
   
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Re: FEMM shows interesting OU effect, the airgap is everything. « Reply #71 on: 2026-07-25, 08:05:31 »
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Just finished an 8 hour data collection run. However it is quite evident it overshoot the area of interest by a lot. Attached you see the flux v. current graph. The core reaches saturation around 50A this time so I must lower the max current sweep by a lot.
The energy data is coarse and unreliable around these lower currents and needs a more refined run but I shared it for completion. Time to start another 8 hour run.
   
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Re: FEMM shows interesting OU effect, the airgap is everything. « Reply #72 on: 2026-07-26, 05:01:31 »

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Quote from: broli on 2026-07-24, 23:04:14
So say input 1A*1Wb/2=0.5J vs 2*(1A*0.7Wb/2)=0.7J
Why 1A ?

Quote from: broli on 2026-07-24, 16:58:50
2) While maintaining a constant current on it you bring the other coil to the same current
and how do you propose to do that? 
You can assume an ideal coil when answering this question because non-ideal coils complicate analysis and don't bring anything beneficial to the table...
   
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Re: FEMM shows interesting OU effect, the airgap is everything. « Reply #73 on: 2026-07-26, 21:18:45 »
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Sadly the new run highlighted a fundamental issue with this solid state design. The COP is essentially one across the tested range. What I did wrong in the math was only consider a drop in saturation field. However the simulation highlights that both saturation field and current drop which in hindsight makes sense really. After including the correct trigonometric value for that then the math also shows perfect unity.

I guess it would have been too good to be true to get rid of the mechanical aspect of this.
   
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Re: FEMM shows interesting OU effect, the airgap is everything. « Reply #74 on: 2026-07-26, 21:23:30 »
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Quote from: Verpies on 2026-07-26, 05:01:31
Why 1A ?
and how do you propose to do that? 
You can assume an ideal coil when answering this question because non-ideal coils complicate analysis and don't bring anything beneficial to the table...

It's just an example value to keep the math simple.  And yes in FEMM these synchronizations are easy to pull off that that is why I am doing the validation in it. If FEMM confirms extra energy then that would be significant as it would imply its fully compatible with EM theory.
   
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