Sealed demo fusor idea
- Emma Black
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- Real name: Emma Black
Sealed demo fusor idea
Separately to my main fusor effort, I have been playing around with a very minimal demo fusor idea, just for fun. A sort of desk ornament sized type of device.
First off using a tiny transformer, AC only and using the plasma itself as a diode i.e. a half wave rectifier.
Then pumping a thick glass tube down and sealing the end like you would an ampule or valve, removing the need for a pump. I'm still very much learning glass blowing at the minute but think I could get a fairly good seal even with the HV feeds. Been making some low pressure ampules for yet another project, which got me thinking.
Would a sealed design work for a demo, I guess getting the pressure just right would be very tricky?
First off using a tiny transformer, AC only and using the plasma itself as a diode i.e. a half wave rectifier.
Then pumping a thick glass tube down and sealing the end like you would an ampule or valve, removing the need for a pump. I'm still very much learning glass blowing at the minute but think I could get a fairly good seal even with the HV feeds. Been making some low pressure ampules for yet another project, which got me thinking.
Would a sealed design work for a demo, I guess getting the pressure just right would be very tricky?
- Richard Hull
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Re: Sealed demo fusor idea
A sealed demo would be possible in theory. However, outgassing and deposition would slowly foul the thing, requiring a possible opening and re-vacuuming and cleaning. It would be a long shot.
Richard Hull
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
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
- Liam David
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Re: Sealed demo fusor idea
You might look into sealed beam-target neutron generators for the vacuum technology needed. Also, many standard vacuum tubes operate for decades with keep-alive plasmas lit, although I must admit my knowledge in that department is almost nil. You'd almost certainly need a getter, and pump the vessel into UHV and bake it at > ~200C for several hours before backfilling with some dry gas.
- Emma Black
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- Real name: Emma Black
Re: Sealed demo fusor idea
This is what I was thinking a getter for absorption is a must, otherwise stuff is just going to build up in the chamber and ruin things really quickly, my knowledge is also very limited in this area.
You could possible run the getter on a separate "cleaning" cycle rather than when the HV is being applied. Material choice would be tricky though, I need to think about the chemistry of whats happening inside the chamber and what would work and then do some experiments.
You could possible run the getter on a separate "cleaning" cycle rather than when the HV is being applied. Material choice would be tricky though, I need to think about the chemistry of whats happening inside the chamber and what would work and then do some experiments.
- Richard Hull
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Re: Sealed demo fusor idea
It is to be remembered that the device, if sealed, is a gas filled bombarder. The admonition about cleanliness is great and the getter idea is also good. My advice is, as always, with new ideas thrown down in these forums..... Do it!... Build it! Test it over time. Then, report back to us on your result, be it success of failure. Let the experiment be done!
Richard Hull
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
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
- Emma Black
- Posts: 197
- Joined: Wed May 11, 2022 9:42 am
- Real name: Emma Black
Re: Sealed demo fusor idea
Oh 100% agree even if it doesn't work I will likely learn something and give others ideas.
- Richard Hull
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Re: Sealed demo fusor idea
That is the true spirit of the scientific endeavor. Now that the idea is fixed, the engineering mindset can take over. This is why this site and these forums are here. They are to grab the interest of the curious and from that point, teach, advise, and support. In the end, that is all we can do. It is up to the verve and drive of the curious to take to the hands-on experience to turn ideas into hardware.
With self-directed study and action, all who come here and achieve even the smallest success or even an instructive failure will be an enriched person of some confidence in themselves.
Richard Hull
With self-directed study and action, all who come here and achieve even the smallest success or even an instructive failure will be an enriched person of some confidence in themselves.
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
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
- Dennis P Brown
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Re: Sealed demo fusor idea
The dry gas should be argon - even nitrogen can disassociate and create a surface film under high voltage in a sealed tube. Helium will tend to diffuse out lowering the pressure so the glow discharge will fail, in time. Basically, you are creating something very similar to a plasma glow ball (popular in the 90's.)
- Emma Black
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- Joined: Wed May 11, 2022 9:42 am
- Real name: Emma Black
Re: Sealed demo fusor idea
Yeah I know exactly what you mean, the very early ones actually used a vacuum and air I believe but had issues with pressure. From the 90's onwards I think they use a mix of gasses at pretty much atmospheric pressure.