Magnetic grid

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Jeroen Vriesman
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Magnetic grid

Post by Jeroen Vriesman »

This grid is made of 24 CoSm magnets, each side of the cube is a magnetic quadrupole.

Still working on pressure control, no star mode yet. The idea is that a particle beam going in and out the cube (star mode) travels in both directions through the quadrupole, which might have an effect similar to "strong focusing".
If that is true, a lower current compared to a non-magnetic grid at the same pressure and voltage might be possible.
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mag_grid_1.png
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Richard Hull
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Re: Magnetic grid

Post by Richard Hull »

Great experiment! I would be amazed if it works as you expect, but I am always prepared to be amazed. Real thermal heating may occur. The curie point of those SmCo magnets is about double that of the best NdFeB magnets, which is a good thing in their favor. You will have to be mindful of this if your fusor is operated at higher power levels.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
jpnms
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Re: Magnetic grid

Post by jpnms »

Great experiment!

I have seen an idea that resemble yours (i attach the URL), but I've never seen the result!

http://www.enu.kz/repository/2010/AIAA-2010-6605.pdf

Good luck!
Jeroen Vriesman
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Re: Magnetic grid

Post by Jeroen Vriesman »

Richard,

indeed I chose CoSm for the high curie point. And I also would be amazed if it works as expected. (and even if the current is lower at the same voltage/pressure I still wouldn't know if my ideas have any relation with reality :) )

Because of the thermal effects I can only use a low current, I'm going to use a GP5 (30kV beam triode) tube to make a constant current source of about 200uA at 20kV (stat is still 4W), to get a stable plasma at such a low current I need a good pressure control system.
The system:

TPH330 + DUO008b pumps
A CF100 open/close valve directly on the TPH330, this will be open during bake-out, closed during operation
A bypass of the CF100 valve with a stepper-motor controlled throttle valve, controlled by an STM32F0-discovery board, getting it's analog input from the anode voltage of the GP5 current source.
A needle valve to let some gas in.
Pfeiffer-balzers full range gauge.
a "swimming pool pump" from a toy shop to circulate the cooling water of hte turbo pump.

the idea is to control the pressure directly with the voltage on the grid.

jpnms: that paper is very optimistic, I only hope to measure a somewhat higher voltage at the same current for the magnetic grid, knowing that even if that is the case, the mechanism behind it is speculative.
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throttle_valve.png
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Richard Hull
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Re: Magnetic grid

Post by Richard Hull »

Every idea is worth a shot if you can afford it and can follow through with some sort of result even if it is a negative one.

Too many ideas are spouted off like senseless machine gun fire and never mechanized. At least, you have already worked up your idea in some sort of hardware and are prepared to follow it out to some sort of conclusion.

Be sure to let us know where this work winds up.

Richard Hull
Progress may have been a good thing once, but it just went on too long. - Yogi Berra
Fusion is the energy of the future....and it always will be
The more complex the idea put forward by the poor amateur, the more likely it will never see embodiment
Roberto Ferrari
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Re: Magnetic grid

Post by Roberto Ferrari »

Hi Jeroen

Nice setup!
Are you aware that some magnet alloys suffer under hydrogen exposure modifying their structure?
Hope your magnets are away of that problem!

Regards

Roberto
Jeroen Vriesman
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Re: Magnetic grid

Post by Jeroen Vriesman »

Roberto,

hydrogenation is a NdFeB problem, CoSm doesn't have this problem.
I use nickel plated CoSm.

http://www.mceproducts.com/Knowledge_Ba ... marium.htm
Roberto Ferrari
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Re: Magnetic grid

Post by Roberto Ferrari »

Great!

Good luck! We wait for your report.

Roberto
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