From the FAQ - In the fusor, good geometrical alignment of the inner grid structure is important. A clean vacuum that is free of organic vapor and, hopefully, water vapor is also desired.
Questions I have - when running a fusor in demo mode -
1) why does a fusor need to be free of organic vapor?
2) why does a fusor need to be free of water vapor?
3) what's this about good geometrical alignment of the inner grid structure being important
Questions about answers to FAQ
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waltsphotos
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Richard Hull
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Re: Questions about answers to FAQ
No fusor now or in future will be free of organic vapor or water vapor. Period! It is on earth and all these will be present in all vacuum systems, forever.
Their relative concentration is another matter. A fusor will operate flawlessly with 10% of its working atmosphere loaded with water and organics. A good, clean fusor will have less than 1% water and organics. A UHV system might have only .0001% of its remnant atmosphere loaded with water or organics. Provided it is pumped with getting rid of these as a main feature of operation. (not an easy task)
Most junk, first pass fusors with mechanical pumps can't even hit 50 microns due to water loads and organics most of which dominate the internal gas.
One only need pump down to 1 micron (10e-3 torr) and back fill to 10 microns with D2 to have less than 10% other gases in a fusor. using a superb trap (micromaze) one can get down to where the water load in under 1% of the gas in the fusor!
Grid concentricity is not hyper important. Eyeball centering is good enough for any purposes of fusion. The anally retentive can use their micrometers if it makes them happy. There is no published emperical data militating flawless concentricity as a fusion booster. However some may choose to obsess over it.
Richard Hull
Their relative concentration is another matter. A fusor will operate flawlessly with 10% of its working atmosphere loaded with water and organics. A good, clean fusor will have less than 1% water and organics. A UHV system might have only .0001% of its remnant atmosphere loaded with water or organics. Provided it is pumped with getting rid of these as a main feature of operation. (not an easy task)
Most junk, first pass fusors with mechanical pumps can't even hit 50 microns due to water loads and organics most of which dominate the internal gas.
One only need pump down to 1 micron (10e-3 torr) and back fill to 10 microns with D2 to have less than 10% other gases in a fusor. using a superb trap (micromaze) one can get down to where the water load in under 1% of the gas in the fusor!
Grid concentricity is not hyper important. Eyeball centering is good enough for any purposes of fusion. The anally retentive can use their micrometers if it makes them happy. There is no published emperical data militating flawless concentricity as a fusion booster. However some may choose to obsess over it.
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
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waltsphotos
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Re: Questions about answers to FAQ
ok let's see if I understand.
the reason fusors need to be relitively free or organic vapor and water vapor, is to achive stronger vacuums/ cleaner D2 fuel.
and an inner grid only needs to be relitively centered and concentric. good geometrical alignment of the inner grid structure really doesn't matter.
~Walt
the reason fusors need to be relitively free or organic vapor and water vapor, is to achive stronger vacuums/ cleaner D2 fuel.
and an inner grid only needs to be relitively centered and concentric. good geometrical alignment of the inner grid structure really doesn't matter.
~Walt
Re: Questions about answers to FAQ
,Walt -
Another way to regard the placement issue is to remember that the potential difference between the inner grid and the outer fusor shell, determines the kinetic energy, and thus the velocity of the gas ions.
So whether the inner grid is precisely centered or not only affects where, the nominal point of ion intersection will be, in relation to fusor's outer shell. It is always somwhere inside the inner grid and actually not very far from the center of that grid.
So the grid can be a bit off-center and the ions will still converge more or less to its center.
Also, as Richard suggests, a simple flush (even up to atmospheric pressure with very dry nitrogen) will dilute the remaining water vapor to a very low level.
What's left of the adsorbed water on surfaces inside, will be quickly scrubbed off by energetic ions, once you get a plasma condition going. Things tend to self-clean if you give them half a chance. It's quite a robust design.
Dave Cooper
Another way to regard the placement issue is to remember that the potential difference between the inner grid and the outer fusor shell, determines the kinetic energy, and thus the velocity of the gas ions.
So whether the inner grid is precisely centered or not only affects where, the nominal point of ion intersection will be, in relation to fusor's outer shell. It is always somwhere inside the inner grid and actually not very far from the center of that grid.
So the grid can be a bit off-center and the ions will still converge more or less to its center.
Also, as Richard suggests, a simple flush (even up to atmospheric pressure with very dry nitrogen) will dilute the remaining water vapor to a very low level.
What's left of the adsorbed water on surfaces inside, will be quickly scrubbed off by energetic ions, once you get a plasma condition going. Things tend to self-clean if you give them half a chance. It's quite a robust design.
Dave Cooper