Check out the new Google Scholar search. Basically Google for peer reviewed journals n' such. I found a couple of interesting IEC fusion articles. It's amazing that such simple search terms turn up a surprising amount of high quality hits. Beats the regular Google any day of the week - well, except for the pay per view nature of these journals, that is.
TANSTAFL.
Electrostatic Inertial Plasma Confinement
Study of Ion Microchannels and IEC Grid Effects Using SIMION Code
Well I replaced 12 2.75", 1 4.5" and 1 6.0" Viton seals with the Teflon gaskets. Even though my finger tips are numb from the star nuts, I must say these gaskets rule. They seat perfectly and they are as smooth as a baby's bottom. In the process of replacing one of the 2.75" ports, it was obvious that the Viton seal was mis-seated. Still gave a decent vacuum (10-6), but I'm glad it's out of there.
So the cage is now unwired from the electrical feed-through. Fundamental laws of topology and conflict with the replacement of the seals on the feedthrough... The main chamber seal still isn't closed until I get the cage reconnected to the electrical feed through. But since I have to use the hoist to do that, I'll leave that task until tomorrow night.
Still, all these gaskets in the system created a large area of out-gassing Viton. Replacing this Viton with Teflon can only be a very, very good thing. I also should remember to get some Everclear to clean up the few fingerprints on the cage. Since I'll have the chamber open and all. . .
Well, the very kind Michael Hettrick has sent my order of Teflon gaskets for the beast and tomorrow I'll go about replacing all the Viton gaskets. The main seal will still be copper, and there will be the one Viton gasket at the base. I'm hoping that since this gasket is at the base, next to the pump, it won't have a huge effect on the pressure of the system - we'll see. Currently I can get the base pressure down to 10-6 Torr. If I can get an order of magnitude decrease in the base pressure, then I should be doing okay.
Moving forward, at least. :)
Well, after a turgid couple of months, I've finally got time to start doing work on the beast again.
There's been a couple of things that have happened that I didn't blog about. On the left is the cage as mounted in the chamber. Click on the image for a larger picture. The magnets are all mounted, and the ceramic stand-offs have been attached. I actually got the detachable electrical connection to the feed through completed as well. Now all that awaits is the actual connection of the wires and a test of first plasma.
Well, that and a lot of work on electron guns and ion guns. From my simulations, I found that just the addition of the magnets on the charged cage is enough to increase the orbits of the ions by an order of magnitude at least. I say "at least" because my simulation is slightly asymmetric. Due to the chopping of space by cubes, the fields aren't as symmetrical as I think the actual cage I constructed are.
In any event, the magnets do an excellent job of changing the momentum of the ion at the physical cage boundary. As you can tell from the potential field diagram, due to the inverse square law nature of electrical fields, there are huge wells leading right into the cage structure. The magnets, which have a field strength of 1.2 Teslas, provide just enough kick to the ions so that there momentum is changed just enough to avoid plunging down the potential gradient and grounding out on the cage structure.
Very cool.
Anyways, I got all the old site moved over, and the various pages linked in. Google should have these indexed and such so that queries for the documents won't find the old site location.
On the right is the cage with magnets and stand-offs, sans chamber. Click on the image for a larger picture. It's actually quite the pretty thing to look at. All shiny from the electropolishing n' such...
The guys at Heat Wave labs still haven't gotten back to me. Likely think I'm a wanker and they don't want to waste their time with me... Oh well, I'll have to phone them and talk to the guy in charge of their electron guns and cathodes.
Yi. Need to transfer more and my disk died...
Will have the old site transfered here soon...
Moving over the old web site to a real blog (i.e. Movable Type). Should have most of it migrated soon, but I have a lot to convert, and no automated way to import it (unless I can figure out the import format for MT... Hmm, there's an idea).
Last
night I changed the SimIon model to use one electrode for the entire cage and
received much better agreement with the five fold symmetry. In the
previous model, each of the great circles was a separate electrode. I know
this was bone headed, as they are all at the same potential, but I won't go into
the reasons why this came about. The extra bonus is that the field
calculation is about half as long. Only two electrodes, not 7. <heh>
I can be silly at times.
Finally
got some time and dug into simulating the beast with SimIon.
Click here to download the SimIon geometry
files. Why was this hard? Just figuring out the three
dimensional rotation matrices, that's all. Tedious, as the SimIon
reference frame is a right handed, and the reference frame I had from my cad
system is left handed. Projection and a few sign changes later and I had
the icosidodecahedron cage modeled as an electrostatic potential array (shown on
the left). Click on the image for the
full size image. It's the standard 3D isometric viewpoint of the
icosi-grid as modeled in SimIon.
Well, Richard Hull should be considered a national treasure. The man is simply the epitome of the stereotype of a truly serious amateur scientist. He is a continual source of amazing information, tireless effort on experiments and a fount of wisdom. He just put out a wonderful post on Neutron Safety that you absolutely must read. You should pretty much search www.fusor.net for the name Richard Hull and you'll see what I mean. Just simply amazing.
Well, everyone seems to be working hard. Me? I'm laying down safety procedures. I've got a gas line spur that I need to get rid of. It was put in for an eventual change from the electric water heater to a gas heated system. Well, that ain't happening anytime soon, as we just replaced the water heater in the great flood of 2002. Basically, some valve broke on the water heater unit and I woke up to 6" of water in the lab @ 6:00am one fine Friday morning. Something like this once happened at UCCS. And like a fool, I waded into it to open the sealed doors so the water can flow out to the drain. Who would build a basement without a drain? Especially a drain by the water heater? Well, that's not the kind of planning one gets from a Hellblazer education.
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