Fusor from Poland

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kubajed
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Real name: Jakub Jędrzejewski

Fusor from Poland

Post by kubajed »

Hi,
in terms of the scientific project, we decided to investigate the phenomenon of a fusion. We started our work by making the fusor. We are cooperating with a local nuclear physics institute to assist in testing and assessing the design of the device before implementation. After consultations, preliminary simulations and comparation with fusors of similar dimensions on the forum fusor.net, we started to perform our one.
The finished device was transported to the institute, where it was connected to the pre-pump, turbomolecular pump, vacuum gauge and the micro-dosing valve. Before the final assembly, the entire device was cleaned with alcohol. The high voltage is supplied by a feedthrough, with a self-made 0-40kV power supply that has a current capacity of over 30 mA. After the first successful ignition of deuterium, we started searching a sweet point, unsuccessfully. Determining the lack of the appropriate methodology, we started sweeping by 2 mTorr step in order to find point of work. We found the working point between 9.5 and 10 mTorr. In this range, the discharge ignites at ~ 35kV and a delicate, almost invisible glow appears in the middle of the grid, which is accompanied by gamma emission (possibly also neutron emission). However, after a few seconds of work, the discharge voltage begins to decrease with the gamma emission and with increasing brightness of the discharge. Everything is accompanied by increasing pressure. Initially, we thought that something of the system is simply gassing, however, due to the use of rubber seals in the system, we can not heat the whole system exactly as we would like to. We heated the grid and we the chamber as much as we could.
The device is made of stainless steel and the grid is made out of copper (on photos another grid). However, the pressure is growing just as fast as before heating. In the present state, the system after starting up is at its point of work only about 5 seconds until the pressure increases too much.
Below you can see graphs that we were able to do.

Technical parameters:
Inner diameter of the chamber: 150
Diameter of the grid: 30
The grid is negative, the chamber is grounded.
We would like to ask you for advices, what we should to do next in order of stabilizing the work of our fusor and making it a source of neutrons.
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Richard Hull
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Re: Fusor from Poland

Post by Richard Hull »

I see what looks like a homemade switching type HV supply. Do you have a ballast resistor in the supply's high voltage line? If not, that is your problem. A potent power supply, if it is really capable of 30ma at 30Kkv into a heavy, unballasted 900 watt load, must be ballasted to operate a fusor.

A fusor is a non-linear gas load and one must work up to the full potential over a period of days. The first day you will have to operate at about 3-4 milli-torr and be fortunate to achieve 25kv in stable long term operation. In short, you get all the x-radiation and no fusion Such action is normal. The second day will be better.

I had a recent long posting on just this subject.

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
kubajed
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Joined: Fri Nov 16, 2018 2:01 pm
Real name: Jakub Jędrzejewski

Re: Fusor from Poland

Post by kubajed »

Yes, we use 1,2 M resistor on HV side.
What do you mean by that?
Richard Hull wrote: Sat Nov 17, 2018 1:11 am The first day you will have to operate at about 3-4 milli-torr and be fortunate to achieve 25kv in stable long term operation. In short, you get all the x-radiation and no fusion Such action is normal. The second day will be better.
Do you mean to turn on the HV, leak 4 mTorr of deuterium and leave it for a day?
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Richard Hull
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Re: Fusor from Poland

Post by Richard Hull »

No. You must find a constant leaked pressure that works with any voltage over a few minutes. Operate it for some minutes and then see if the next day you can do better.

You must read my recent posting on how to condition a fusor.

viewtopic.php?f=6&t=12453

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
kubajed
Posts: 4
Joined: Fri Nov 16, 2018 2:01 pm
Real name: Jakub Jędrzejewski

Re: Fusor from Poland

Post by kubajed »

Ok, thank you. I read your article, but I am still unsure what I shall to do. The main problem we have is a growing of the pressure. Every time it is rising up after ignition, so it is impossible to maintain a constant pressure.
John Futter
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Re: Fusor from Poland

Post by John Futter »

I suggest changing your gas to Argon and run at around 10kV or below to glow clean the interior of your fusor
and couple of hours of this in timed runs so as to not heat the chamber too much then change back to D2 and see what happens
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Richard Hull
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Re: Fusor from Poland

Post by Richard Hull »

John apparently thinks you have a chamber whose walls are horribly loaded with water and other gases. If so, you do need to glow clean the system as he suggests.

I hope your supply is smoothly variable from zero volts to its full potential while operating. This is very important.

Typically, you first get a stable pressure in the chamber. Start at 4 microns. next, you raise the voltage very slowly until the plasma strikes and immediately reduce the voltage smoothly back down, maintaining the glow insuring that the current is stable at this reduced voltage. If the current starts to climb a bit, slowly lower the voltage, yet again, to keep the current stable. Once you have a stable pressure and current, just let the fusor cook and heat the walls of the chamber.

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
kubajed
Posts: 4
Joined: Fri Nov 16, 2018 2:01 pm
Real name: Jakub Jędrzejewski

Re: Fusor from Poland

Post by kubajed »

Ok, we will try it. We have just upgraded our power supply up to 60 kV (yes, it is changeable from 0 to 60 kV) and we are going to make our measurements fully digital and wireless.
Rex Allers
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Re: Fusor from Poland

Post by Rex Allers »

Acting as net nanny... You should post in Please Introduce Yourself section (per forum rules, it should have been your first post.)

Also, per rules, your name should be your full real name, not a shortened tag. Please edit your account settings to change your user name. Your posts will remain but your login will change to the new name.

You made a very nice, detailed post here, but mainly it is just looking for notes on your particular implementation. I think it would have been better in Images du Jour section. Other questions of the nature of, "is this the best way" or "how do I", are best in the New User Chat Area.

Sorry to be critical, your post was very well made, but you should read and follow the rules. Look at "Announcements and Site Administration Topics" "Fusor.Net Policies and Procedures". This info was also presented when you registered and you agreed to it then.
Rex Allers
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