Hello Craigy,

Hello guys.

How do you calculate the strength of the magnetic field in a coil?

Suppose you wind a coil 10 turns at 0.01 ohms resistance and run
31.6 amps through the coil which gives you 10 watts.
Will the magnetic field be just as strong as if you had a coil
with 1000 turns at 1 ohm and run 3.16 amps throung it = 10W

It is the same 10 watts but will the increased turns give stronger magnetic field?

I'm asking this because the low turn coil will be a low inductance coil,
which has greatly reduced delay time when activating the magnetic field.

Thank you very much for a fast and great answer.

Do you know how to wind a coil to achieve strong magnetic fields at low inductance?

There are numerous ways to wind coils, but which one is best when I want low
inductance but strong fields?

Yes, but all we are interested in is if this valve has a use. Think about it, If we can build an electromagnet(using the same power to the coils as the valve) of the same dimensions as the valve  and get the same effect, the valve is not more efficient than an electromagnet. in which case overunity is highly unlikely.

Hi Albert,

Why cannot you understand that in Jack's valve the flux from the permanent magnet is added to the flux from the electromagnet? And if you accept the fact that Jack figured out how much input power is needed for the electromagnet in his valve to quasi double the flux of the built-in permanent magnet you realize that it is just about 8W input that is needed for him in that valve, considering the grade and size of his Neo magnet, the cross section of his full magnetic path etc.  Jack achieved this in practice and not by a 2-dimensional simulator, ok?  And if you wish to eliminate the permanent magnet from his valve then you simply build a normal electromagnet (being all the other data/dimentions are maintained) and you will never receive the double flux field in PRACTICE, ok?
So this valve is not about using a permanent magnet together with an electromagnet completely superfluously.

In other words, imagine you have an electromagnet, and you remove a portion of the core and replace it with a magnet, and then find it functions exactly the same as before with no increase in efficiency or useability, why would you bother to insert the magnet.  What I'm interested in is, if what has been shown in the sims is also true in real life.

Please read my previous letter to you from yesterday and try to understand it, no use if I repeat it again. You seem to ignore what I wrote or asked.
EVEN Your own simulations show an increase in force (your Picture 1 and 3) so the summing up of the two fluxes is justified by your simulator too. If you understand the flux additions done by the parallel path technique then the SAME happens in Jack's valve but in a completely different mechanical setup.

Regards

Gyula

Hi gyulasun,

Why cannot you understand that in Jack's valve the flux from the permanent magnet is added to the flux from the electromagnet?

I do understand this. My point is that the same effect is achieved with a block of iron replacing the magnet( at least in the sims).

And if you wish to eliminate the permanent magnet from his valve then you simply build a normal electromagnet (being all the other data/dimentions are maintained) and you will never receive the double flux field in PRACTICE, ok?

Ah, are you so sure about this? the simulation shows exactly that in pic2( with the magnet replaced with a block of iron, and same coil and electric input), that is why I'm so interested if that is the case in real life.   Doesn't it bother you that a block of iron does the same job as the magnet? just build the valve with a block of iron instead of the magnet, after all, iron is cheaper than magnets,    oh, but then we would have a simple electromagnet that produces the same force from the same electro input then and not a magnetic valve........ when you look at it this way you can see that overunity is not going to be possible.

I look forward to seeing published results of an independent test of Jack's motor.



Thanks for taking the time to try and put your point across Gyula, however, I believe you and I think in very different ways, and until I see a test of the valve with the magnet replaced with a block of iron, then I think the idea is flawed.

regards

Albert

....If I want to wind a electromagnetic coil with an soft iron core that gives 1 Tesla
at a certain voltage how do I calculate the number of turns needed?

Hi Honk,

There is a formula here:
http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/elemag.html#c5  but it includes a 'misprint' I think. Correct formula is B=u*n*I  where u=k*u_o and k=relative permeability of your core and u_o=4*pi*10^-7

You may find the normal solenoid formula here where it seems correct:
http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/solenoid.html#c3  and you may find the meanings of n too.

Regarding the wire diameter it is dictated by the current it is needed to carry, the space it occupies or how much room is available for the coil, surely a trade off between space and copper loss.

Regards
Gyula

Quote from: acp on February 08, 2007, 10:22:24 AM

I do understand this. My point is that the same effect is achieved with a block of iron replacing the magnet( at least in the sims). ?

Now if you insert a block of iron into the empty part of the previous sleeve you have just increased manyfold the original 'A' effective cross section area of the sleeve and this is the ONLY explanation why you got 3000 Newton force in your picture #2!!!

This is why I do not bother that your block of iron 'does the same job' as the permanent magnet, for it DOES IT WITH AN HIGHER CROSS SECTION AREA WHICH DOES COUNT IN THE RESULTANT FORCE OF AN ELECTROMAGNET!

Regards
Gyula

Albert got it right.

If replacing the magnet with a pice of iron in the real world, not FEMM, and the output
is the same as when using a magnet, then we can kiss Over Unity goodbye.
Because the iron magnet valve will have the same size properties as the one with
a magnet, and this tells us that we don't get extra energy from the magnet.
And if we don't get any extra energy then we can ditch this motor as the holy graal.

End of discussion.....

Unless we can test the valve in real world with a piece of iron replacing the magnet. Then we can see if there is any difference or not.
It's all about being able to make use of the energy from the magnet. No matter what.
If an electro magnet at the same size and shape as the magnetic valve gives the same output power then there is no way we get a self runner.

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Bye the way, I'm a believer in Jacks motor and valve.
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