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What we're missing

Posted: Sun Mar 12, 2006 9:17 pm
by HighVoltageFox
I was recently reviewing the Farnsworth Files and found that Farnsworth reached self-sustaining fusion some where around the power of 150Kv @ 70mA. It seems to me that self-sustained fusion would be able to make break even very possible in the small fusors made in this group. I am getting a qoutes on a 200Kv @ 100mA power supplies, if I can find one cheap enough I might be able to get a loan.
If we go back to the design Farnworth last made before his death we may be able to complete his dream. Sure its a long shot but if someone or a group can recreate the self-sustained fusion that Farnsworth saw then it is completly possible to use fusion for power. It would be difficult to recreate and then improve the design, but isn't it worth it?
I know that shealding, feed-throughs, and grid design will pose a problem at such voltage and amperages but these can be over come. And my idea to improve the grids resistance to heat is to use a heavy metal oxide on an already high melting point metal. Is would improve the run time. And if tritium was used there is a possiblity that the tritium made in working fusors could be seperated from the He3. Right?
Does anyone else think that this is possible? Anything that could make such a feat impossible or improbible? Any suggestions or things to add? Anything I over looked?

Andrew Hahn

Re: What we're missing

Posted: Sun Mar 12, 2006 9:55 pm
by Richard Hester
Check past posts - the self sustaining story is a tall tale.
Not enough tritium is manufactured in a fusor to make its separation worthwhile. Even at a rate of 10^10 reactions/second (preposterous for an amateur, dangerous to life), tritium production does not even come close to molar quantities.

Re: What we're missing

Posted: Sun Mar 12, 2006 9:57 pm
by winterhaven
Hi Andrew,
The "self sustained" reaction that you're talking about is pretty controversial. Personally it sounds to me like it was more a case of equipment error, and it was never confirmed or duplicated.
There has been some discussion of this here on the forum. Do a search for "run away" or "runaway" or possibly "sustained" along with "Farnsworth" and you should come up with it I think. Give it a read and judge for yourself.


Re: What we're missing

Posted: Mon Mar 13, 2006 1:19 am
by HighVoltageFox
Well even if it is controversial, what would I lose besides spending a little on equiptment. At the worst I would disprove Farnsworths readings and stop the controversy. I dont know if tritium is the real key to such a reaction, which I doubt it is. But just for grins does anyone know what hoops the government requires you go through to get a licence for it?

I don't know much about the debates over whether Farnsworth produced self-sustained fusion, but I would think that a logical, truthful man like Farnsworth would generally know what he's talking and wouldn't use such a lie to get publicity or funding. Ofcourse I only know him through accounts in books so I could be completely wrong.
And what laws of science say that fusion cannot self sustain in a fusor? Is there something I am missing, is there a law that would not allow this to occur?
I am not focusing on how to get power from a fusor, just the possiblity of self-sustained fusion. What theories do you guys have about self sustaining fusion?

Re: What we're missing

Posted: Mon Mar 13, 2006 3:24 am
by winterhaven
If a power producing fusor is possible, I think that "self sustaining" is generally a bad way to descrbe what would probably be happening in the reaction chamber. More power out than in is probably a better description of how it might work. The reason for this is that if a reaction occurs, the kinetic energy of the particles will most likely fly right past all the other fuel and slam into the walls and not impart any of it's energy to the rest of the gas, this is because at these low pressures the mean free path is so great that they probably won't strike any of the other particles. This goes extra for any neutrons frrom the reaction since they are neutrally charged, in fact they probably won't be stopped by the chamber walls either.
The information above and also what I've read on this forum about the "sustained" Farnsworth fusor incident makes me think that it just didn't happen, and also makes me think that it's not even possible with any of the configurations pioneered by Farnsworth.
As far as Tritium goes, that's been discussed recently also, and the phrase that comes to mind is; it sounds like a bitch to get any kind of licence for it's use - especially for any kind of nuclear reaction purposes!

geez I've been posting here long enough that I'm becoming almost as much of a wet blanket as Richard Hull ; )
But you know, there's a lot of good info here, and none of us wants to see anyone try an elaborate idea without being totally informed of the background info that is available or throwing in our 2 cents if it's asked for.


Re: What we're missing

Posted: Mon Mar 13, 2006 3:52 am
by Andrew Seltzman
Even if you could find such a supply 200kV at 100mA is 20KW of power on the output, you would have a very hard time powering the supply. Thats approximatly 150A at 120V or 75A at 240V

Andrew Seltzman

Re: What we're missing

Posted: Mon Mar 13, 2006 4:10 am
by AnGuy
>And what laws of science say that fusion cannot self sustain in a fusor? Is there something I am missing, is there a law that would not allow this to occur?

The fusor requires a high voltage source to contain the hot plasma. In any environment, hot plasma wants to expand and disappate. In an operating fusor, the High voltage source acts as a container forcing the plasma toward the center where deuterium ions can collide and fuse. The Fusor also works like a particle accelerator by creating ions from gases contained in side of the vaccum chamber. The Ions are attracted to the high voltage inner grid and causes the ions to accelerate and obtain a high enough velocity to cause fusion when two ions collide. The Vacuum walls cannot function as a plasma container because the walls would rapidly cool and deaccelerate any ions that strike its surface.

Its highly improbable that a self sustaining fusion reaction can occur without a voltage source applied to contain the hot plasma.

Re: What we're missing

Posted: Mon Mar 13, 2006 7:02 am
by winterhaven
I think the word containment is another one that is not really applicable to the fusor. There is the poissor area that tends to glow, and I believe this is an area of higher density, but the ions are in this area for a very, very short time, and thus, no real confinement.
There's been some talk of ions spiraling around the grid wires, which might be seen as a type of confinement, but no one's really sure to what extent that happens, I tend to think it's more the exception than the rule, and probably only with lower energy ions i.e. < fusion energies. I think that more of the ions collide with the grid than spiral around but that's just my opinion.


Re: What we're missing

Posted: Mon Mar 13, 2006 3:26 pm
by Richard Hull
Todd has the right picture.

There is nowwhere extant, in any official company documents that have been presented, any mention of self sustaining reactions at the ITT plant on Pontiac Street in Fort Wayne....Period.

There is a one direct statement by one living observer who believes they had a runaway. No one alive who was on the team, save this one individual beleives they had a runaway or self-sustaining fusion. I have personally intereviewed, in person, face-to-face, and on the phone, all of them!

Ignition or self sustained operation brings with it the notion that the fuel is burned at a prodigious rate (as fast as it is introduced into the chamber) Turn off the fuel and the reaction ceases. If this were ever the case all present would be dead and the fusor vessel ruptured, even if the fusion plasma reaction was totally contained.

We are back to just hoping that power in versus power out can look better. As Todd and others have noted.

Finally, consider only 100 watts into a fusor and 100 watts of fusion out..... 100% efficient with no power gain at all.

1. The human torso cross section is ~0.5 sq. meters.
2. Assume you are 2 meters from the working fusor which is taking in and putting out as much power as a good desk reading lamp.
3. At 2 meters, your torso is a relative cross section of 3% of the isotropic emission sphere.
4. Only 1/2 of the fusion radiation will hit you, as the protons created will stay in the vessel. You will receive 1.5 watts of fast neutrons to your torso. Virtually all will react inside you.
5. The Roentgen is equal to ~258 microcoulombs of energy deposited one killogram of body tissue.
6. Let us say that the torso on a normal human is about 45kg.
7. The 1.5 watts of neutrons hitting you will deposit an absobed dose of about (1.5 / 2.58 X10e-4)/45 or ~130 roentgens of radiation to your tissue each second! You would have about 4 seconds before you would exceed the expected lethal dose.

Even a barely break even fusor, operating at only 100 watts, would be lethal. Over unity operation would be even worse.

You were discussing 200 kv @ 100 mils. That is 20 kw! You better hope you are not successful in your quest.

Richard Hull

Re: What we're missing

Posted: Sat Apr 01, 2006 7:58 pm
by longstreet
In the ideal case where you only deal with ions with less energy than your voltage potential and ignore grid collisions, you can say they are contained. I would define selfsustained as reusing the energy from fusion to raise the energy of non-fused ions. The only way this will happen is if the fusion products stay inside the chamber freely flying around to hit other ions, which means the products must be contained. Right away you can see that without megavolts of potential that is impossible even in this ideal case. And impossible no matter for neutron products.