New Anode Cooling 'Limits' Likely

[Aeronaut]

Since the DPF design process hinges on how much heat can be removed from how small of an anode radius/area, I decided to verify Eric’s number regarding heat removal ceilings. What I found was an off-the-shelf heat pipe which I think is titanium (melts at a little over 3,000 F) and uses Lithium as the working fluid.

I did a preliminary design drawing (http://energymadecleanly.com/anode.pdf) exploring using this part as well as asking about the preferred berylium/helium construction for FF generators. I just talked with a sales rep and expect some feedback from their engineers tomorrow around this time.

If this works, we’re free to run it at much higher temperatures, decrease anode radius, raise field strength, reduce rundown time, (more energy to the plasmoid), and hopefully slash X-ray production to below 25% of total charged particle output. The X-ray part is a wild hope, since Eric’s tables don’t show field strength affecting it very much.

What think?

[Brian H]

Aeronaut wrote: Since the DPF design process hinges on how much heat can be removed from how small of an anode radius/area, I decided to verify Eric’s number regarding heat removal ceilings. What I found was an off-the-shelf heat pipe which I think is titanium (melts at a little over 3,000 F) and uses Lithium as the working fluid.

I did a preliminary design drawing (http://energymadecleanly.com/anode.pdf) exploring using this part as well as asking about the preferred berylium/helium construction for FF generators. I just talked with a sales rep and expect some feedback from their engineers tomorrow around this time.

If this works, we’re free to run it at much higher temperatures, decrease anode radius, raise field strength, reduce rundown time, (more energy to the plasmoid), and hopefully slash X-ray production to below 25% of total charged particle output. The X-ray part is a wild hope, since Eric’s tables don’t show field strength affecting it very much.

What think?

Off-the-shelf is very good, of course!
What was the feedback?
And what’s this “LITIUM” stuff mentioned on the drawing? 😉

[Aeronaut]

Brian H wrote:

Since the DPF design process hinges on how much heat can be removed from how small of an anode radius/area, I decided to verify Eric’s number regarding heat removal ceilings. What I found was an off-the-shelf heat pipe which I think is titanium (melts at a little over 3,000 F) and uses Lithium as the working fluid.

I did a preliminary design drawing (http://energymadecleanly.com/anode.pdf) exploring using this part as well as asking about the preferred berylium/helium construction for FF generators. I just talked with a sales rep and expect some feedback from their engineers tomorrow around this time.

If this works, we’re free to run it at much higher temperatures, decrease anode radius, raise field strength, reduce rundown time, (more energy to the plasmoid), and hopefully slash X-ray production to below 25% of total charged particle output. The X-ray part is a wild hope, since Eric’s tables don’t show field strength affecting it very much.

What think?

Off-the-shelf is very good, of course!
What was the feedback?
And what’s this “LITIUM” stuff mentioned on the drawing? 😉

Sorry about the smelling. Should have been lithium, of course. Haven’t heard back from that division. I’ll call the main company Monday. Biggest question in my mind right now is if they make one that’s electrically insulating. Otherwise my heat exchanger has to use liquid silicone, like Eric recommends in the patent for cooling the onion.

How’re the Olympics going? Looks like you’ve got a ringside seat 🙂

[Brian H]

Aeronaut wrote:

…

Off-the-shelf is very good, of course!
What was the feedback?
And what’s this “LITIUM” stuff mentioned on the drawing? 😉

Sorry about the smelling. Should have been lithium, of course. Haven’t heard back from that division. I’ll call the main company Monday. Biggest question in my mind right now is if they make one that’s electrically insulating. Otherwise my heat exchanger has to use liquid silicone, like Eric recommends in the patent for cooling the onion.

How’re the Olympics going? Looks like you’ve got a ringside seat 🙂

Silicone? Hadn’t seen that. Silicon? Nasty stuff. {P.S. was sleepy when I wrote that; was thinking of sodium for some reason! Duh.}

Olympics? Actual seats are going for bigger bucks than I have. :down: I’m just a TV spectator. Parts of the city are busy and heavily involved, but I’m almost out in the ‘burbs, so would need to go looking for action!

[Aeronaut]

I haven’t actually checked into data sheets for silicon(e) coolant. But from what I’ve seen, none of the Borane family plays nice, either. The downside of pentaborane is that it reacts violently with air, which leads me to expect at least a double-walled fuel/valving design to keep it reasonably safe for highly trained servicing personnel. Probably nitrogen charged outer shell and pressure gauge.

But maybe a pressurized fuel system would only need an actual vacuum for the first shot of any run session.

[Henning]

Silicon and Silicone are completely different stuffs. One’s the element, the other one is the rubber. And I don’t remember reading anything in the patent application about them as coolants. They are both not useful here anyway. Both consisting of Si (Silicon) with an atomic number of 14, so pretty opaque to x-rays.

Lithium on the other hand melts at 180° and boils at 1342°C. With Decaborane melting at 99°C and boiling at 213°C, that makes Lithium a pretty good candidate. Also with its 3 protons, that’s pretty much invisible to x-rays – even better than the surrounding Beryllium.

[Henning]

As I’ve seen on your drawing, you suggest to “snug fit” the cooling pipes into the anode. Don’t snug any pipes into the anode, the anode is the pipe itself. Same thing, drilled holes from bottom to top with the cap on (the coolant shouldn’t spill into the vacuum chamber).

Actually not drilled at all, because you can’t drill a hole that turns in the end. Much better for that is laser sintering. The Wikipedia article doesn’t mention Beryllium as commonly used material, so that needs to be developed. Maybe it needs to be sintered in a protective atmosphere (N, He, or whatever).

So some info about materials they’re using currently: http://www.eos.info/en/products/materials/materials-for-metal-systems.html
And a turbine as a result: http://www.eos.info/en/applications/aerospace.html

Oh, and I just read Beryllium melts at 1287°C, so that’s below the boiling point of Lithium of 1342°C.

[Henning]

And here is a promotional video linked how it’s done: http://www.eos.info/en/applications/tooling.html

[Aeronaut]

Henning wrote: Silicon and Silicone are completely different stuffs. One’s the element, the other one is the rubber. And I don’t remember reading anything in the patent application about them as coolants. They are both not useful here anyway. Both consisting of Si (Silicon) with an atomic number of 14, so pretty opaque to x-rays.

Lithium on the other hand melts at 180° and boils at 1342°C. With Decaborane melting at 99°C and boiling at 213°C, that makes Lithium a pretty good candidate. Also with its 3 protons, that’s pretty much invisible to x-rays – even better than the surrounding Beryllium.

Thanx for the insights, Henning, especially about how the protons affect opacity.

I got the idea for the silicone coolant from the patent in section 29, paragraph 3 (last section before the claims), which says “In the case of the X-ray conversion system, however, care must be taken to avoid blocking the X-rays or electrons with the coolant itself by passing an electrically non-conducting coolant, such as silicone, through several dozen very narrow pairs of plates, all oriented radially toward the plasmoid.” So yes, it does attenuate X-rays.

Eric’s focus is on selling cheap electricity using an elegant solution to recovering Bremstrahlung X-rays. This locks him into berylium/helium which limits the thermal output.

My focus is on selling cheap heat- hopefully enough to flash into super-heated ~3000F steam suitable for replacing coal-fired baseload generator boilers using only 1 or 2 FFs in series. I know this is ridiculous to us, but it’s easier for business and political leaders ( golden rule ) to visualize in use and threatens fewer jobs while offering the potential to create LOTS of jobs.

So I’m not worried about the X-rays, except how to jack B so high that the X-rays don’t figure significantly in the machine’s energy budgets. B is a function of anode radius, so using Titanium in this scenario should give derivatives of my design process a lot more maneuvering room.

Many universities, such as Cornell and Michigan State University, use a combined heat and power plant but still have enormous coal bills that can be leveraged to minimize the apparent business risk to present to alumni to get private funding for at least one DPF lab. This way they wouldn’t threaten government funding for DT fusion research. Dang, this para probably belongs in a different category!

As you can see in anode.pdf, the end of the heat pipes are going to be part of the anode circuit, so I need to find a suitable non-conducting coolant that can be moved fast enough to handle whatever heat an engineering lab can send down the pipe.

edit- reading the sintering article 🙂

[Aeronaut]

WOW! Just the 1st para looks like the machine I’ve been looking for over in the CVD marketplace. It also gave me some ideas for the onion, since it should be able to handle a drum-shaped blank.

[Aeronaut]

Yes, they do have my material. It and their machine are already aerospace and bioscience certified: http://www.eos.info/en/products/materials/materials-for-metal-systems/eos-titanium-ti64.html

So it looks like I can design the heat pipe(s) directly into the anode walls. And without drilling, I can design it as a series of coils, not necessarily tubes. Matter of fact, that’s starting to sound like the ion converter. If it’ll do insulating layers via a second powder feed, it should even be capable of building onions.

Thanx again, Henning.

[Henning]

Uh-Oh, didn’t think about electrically conductance. The more mass you’re charging, the worse it gets. So you’ll probably even get sparks outside the vacuum chamber at the cooling plates. So either use a non-conducting coolant (as in the patent), or insulate the cooling mechanism properly, and hope that the additionally mass that needs to be charged by the capacitors doesn’t affect the current rise time.

Some interesting data like “Coefficient of thermal expansion” on Beryllium and Lithium, including prices for research quantities, (we’ll pretty much need those Beryllium flakes at EUR 1518 per 100g, but in dust form).

Some more info about Beryllium dust: it’s toxic (like asbestos), and explosive with nitrogen or oxygen.

[Henning]

I still don’t get why you want to fit heat pipes made out of Titanium into the anode. Or do you mean actually manufacture the anode out of Titanium? Beryllium itself is quite a good heat conductor, even better than Lithium, just that Lithium melts at a lower temperature and thus is able to transport heat as a liquid.

[Henning]

Oh, that “I still don’t get” thing sounds like “I still don’t get what the hell you’re saying”. Wasn’t intended as such, I really appreciate your input, Aeronaut.

[Aeronaut]

Henning wrote: Uh-Oh, didn’t think about electrically conductance. The more mass you’re charging, the worse it gets. So you’ll probably even get sparks outside the vacuum chamber at the cooling plates. So either use a non-conducting coolant (as in the patent), or insulate the cooling mechanism properly, and hope that the additionally mass that needs to be charged by the capacitors doesn’t affect the current rise time.

Some interesting data like “Coefficient of thermal expansion” on Beryllium and Lithium, including prices for research quantities, (we’ll pretty much need those Beryllium flakes at EUR 1518 per 100g, but in dust form).

Some more info about Beryllium dust: it’s toxic (like asbestos), and explosive with nitrogen or oxygen.

Yes, the inductance would be my next major concern following an electrically insulating coolant. The part of the tubes that heat the coolant would be at anode potential, but as long as there’s no cavitation, we (hopefully) won’t have a sparking problem.

I did some contracting at a beryllium processing plant a few years ago, so I never did like the idea of making it a key ingredient. Seems the ultra-fine dust cuts up your lungs, so the entire town downwind has a class-action lawsuit against that company. The bright side is that we can buy it in ingots for a lot less than research prices.

Maybe the inductance fo each tube’s protrusion is “additive” like it is in the cathodes- 1/L1 + 1/L2 + 1/Ln…. 😉

[Author]

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