And digging we keep on doing. The previous designs all lead to unity but it opened new insights and better understanding. Here is the latest design in trying to exploit the electron spin. Say you had a coil which you could stretch out to make longer. What would happen? Well to keep things simple lets consider a coil made out of two layers so we can translate one layer of it to essentially double its length. Additionally lets say you hold the current constant during translation.  FEMM shows interesting OU effect, the airgap is everything. When you do this you will experience a force against said translation which requires you to do mechanical work to essentially stretch out the coil. Magnetically this would roughly lead to halving of the flux in the coil since we didn't change the current or # of windings only its length. Also since we keep the current constant during translation this would lead to pumping electrical energy back into the source. However the full round trip energy bookkeeping will conclude that the electrical energy gained will be exactly compensated by the mechanical work required to lengthen the coil. So perfect unity. However what if we added a ferromagnetic material to this system. Consider this core material to be made out of long individual strips rather than one solid core. Again we magnetize the coil which will now also magnetize the core. And again we pull out the coil and this time we also pull out half of the core strips with it. What will happen now? You might naively state that this is exactly the same situation as before since all we did was change the relative permeability of the system so everything just multiples by said factor and the energy book keeping will ultimately lead to the same balance.  FEMM shows interesting OU effect, the airgap is everything. However there is one major flaw with that reasoning. Yes the coil-on-coil interaction remains the same. But the cores don't mechanically act like coils. In fact they do opposite thing. Their forces actually point in the direction of motion and thus assist the translation!  FEMM shows interesting OU effect, the airgap is everything. So now we have this uncomfortable situation where during the separation the flux is dropping so we are pumping energy back to the source just like we did before with the coreless coil. However mechanically we have a different story as we are now gaining mechanical energy because the core pieces are essentially pushing each other out rather than wanting to remain stuck to their neighbors. If you are not convinced by that here is a quick FEMM simulation showing an array of magnets that are all aligned in the same direction but half of them have been translated. As you can see their force is pointing in the positive x direction.  FEMM shows interesting OU effect, the airgap is everything. This of course does not represent the described system but at least hints at an interesting behavior. I also came to this conclusion from a completely different design but I wanted to lay the groundwork and use the simplest possible design to explain it.
« Last Edit: 2026-08-07, 13:39:13 by broli »
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Topic: FEMM shows interesting OU effect, the airgap is everything. (Read 19143 times)
