[Aeronaut]

I just read a Non Disclosure Agreement that would essentially give that company all rights to the anode design for 5 years. Essentially making them the sole source, thus having no control over pricing or production. Can’t fault them for asking, since I’d do the same thing from their side of the table.

But what’s possible in a commercial R&D company vs what’s possible in the math, physics, and engineering departments of several state universities competing for Fusion Milestone Prizes and the prestige that goes with each leads me to suspect that allowing a commercial engineering company to set the limits on our cooling system components (yes, I implied that they might design in several performance stages) is not going to get us the most design and production flexibility.

In short, I’m proceeding on the assumptions of 1.27cm titanium anode radius ~4 to 8 cm long absorbing a minimum of 500J per pulse, with frequencies as high as 1 Mhz using a pair of DPFs in switched parallel to store the cap bank’s initial pulse energy, plus ion energy gain, something like a tank circuit that may need some makeup energy as well. Fuel is back to decaborane, if not hydrogen and boron mixed in the fuel injector(s). If that can make commercial amounts of superheated steam from a handful of DPFs, we have a clear technical winner that at least resembles what the real world might be willing to invest heavily in. The political wrangling can come later, but will be required once we’re showing progress above unity.

The tank circuit would eliminate cap bank design life as an operating consideration. I don’t think anode cooling is going to be as daunting as it looked to me last week. And I believe we can shield 2 or more units in an oval water jacket with each core (about the size, shape, and weight of a torpedo) only a few inches apart, since each would be active while the other was removing its heat. Since this is a design study with an eye towards Michigan style mass production, my major goals are ballpark parameters, rather than actual engineering.

[Aeronaut]

Breakable wrote: Here is Bill Gates video
http://www.ted.com/talks/bill_gates.html

He specifically ruled out fusion, unless it does better than he expects. (~9:00 into presentation). Nothing succeeds like success, iow, and fission has it, along with an established industry.

[Aeronaut]

I just got initial feedback from an engineer. Seems we can design an annular (hollow core) design using titanium and lithium. Right now the dimensions are anybody’s guess- next step is ask for a NDA, and hopefully get a series of curves outlining what’s likely to be possible.

[Aeronaut]

I doubt we have to worry about that in our lifetimes. Just take a look at all the pies that Babcock & Wilcox, Foster-Wheeler, and Bechtel have their hands in. :smirk:

[Aeronaut]

Around 10 years ago it was El Nino that was screwing up the weather. Perceptions of the masses are managed- bought, sold, traded, etc.

But the bottom line for this thread and the GW threads is that the single most important thing that we can do about all of the world’s challenges that rely on cheap, clean, and abundant energy is to get ff built and deployed in huge numbers. The ripple effects are going to be wondermous to behold. 🙂

[Aeronaut]

Henning wrote: There’s another technique called “Electron Beam Melting” (EBM): http://en.wikipedia.org/wiki/Electron_beam_melting

It’s done in vacuum, so no corrosion problem with air.

And they already tested it with Beryllium (that is AlBeMet): http://www.arcam.com/technology/ebm-materials.aspx

But still only one material.

Outstanding! Now we can optimize for both modes- thermal or electric with rapid prototyping tools to test all the ratio and geometry variations.

The laser sintering demo flick that I looked at yesterday showed a machine that was optimized for prototyping, rather than serial production. Seems that it would be relatively easy to add robotic material feeds and masks, since its all controlled from a CAD drawing.

I goofed yesterday when I said using a few DPFs to make superheated steam was ridiculous. It turns out to be the most cost-effective way to deploy FF. Considering that Rematog conservatively estimated it would take 100 FFs to repower just one of his 3 boilers using 5MW FFs, the entire 1.6GW project would cost around $300M before engineering studies and structural modifications if you plan to re-use the existing building.

Now, if as few as 2, or as many as 60 thermally-optimized FFs can make that much superheated steam, we gain at least a 5:1 price advantage over last year’s price estimates, which also risk being too cheap for credibility. Looks like I have to learn about superheated steam and once-through boilers this week.

Update- ArCam works with many materials, although they’re still certifying the more popular metals. But if you click their auxiliary equipment tab, you’ll see what looks like a sandblast cabinet and read that the powder is blasted onto the surface. That implies a screw-type industrial air compressor and poor control over each layer. Still, it’s nice to know about. Could be a great way to build cathodes en masse.

[Aeronaut]

vansig wrote:

Just a matter of finding out how to build 40000 klicks of carbon nanotube cable that weighs less than a conventional rocket can carry and you’re halfway there.

What’s this i hear about colossal carbon tubes being a better choice for tether material? they’re already macroscopic, and when you look at breaking length, they exceed nanotubes because they are less dense.

http://en.wikipedia.org/wiki/Colossal_carbon_tube

Looks good at first glance. The last sentence says it’s strong enough, and I’m reading the ability to make very long continuous lengths into the article. 69,000 miles long, though, is still going to be a BIG spool or few. But at least that would move the engineering from the tether to deploying the tether. Much nicer challenge to have.

[Aeronaut]

Henning wrote: Hm, about manufacturing the onion with rapid prototyping, I don’t think that’s feasible, because that would repeat the process 2000 times for 1000 layers of conducting foil. It already takes a few hours for each process, even with speeding it up it’s unrealistic. Possibly just build the onion’s skeletal features, it’s cooling coils, and then apply the foil layers by hand. Or spray them onto it. Or more likely spray the insulator, and layer the conductor.

Our pleasure, Aaron. Got a revised sketch at http://energymadecleanly.com/anode1.pdf

Henning, the biggest single challenge of building onions in any quantity is going to be to get an indexing drum within a 2 powder laser sinterer or 2 material CVD machine without ‘overspray’. Given a mochine that can do that, we put several thousand of them in the 2M sq ft Government Motors plant up in Grand Rapids that Brian, Rematog, and I were discussing about a year ago. No reason not to build on the east side of that building and prove along the west side, away from housing and traffic, but closest to those 6 regional transmission lines that we could tee into 12 lines by putting transmission transformers in the west parking lot.

Given the state of the art as I understand it, we’d need to put several thousand CVDs shoulder to shoulder, passing off in a continuous series of vacuum locks without losing registration or browning out that part of the city.

Keep your eye on the toolmakers’ trade shows. No telling what we get for Christmas this year 😉

[Aeronaut]

Yep, a titanium heat pipe anode is hot enough and strong enough to reduce the anode diameter, thus the cathode diameter, which should significantly increase peak field strength and hopefully significantly reduce Bremstrahlung. This approach plays naturally to the machine’s inherent desire to make heat rather than electricity.

[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…. 😉

[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.

[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]

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]

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.

[Aeronaut]

JesterX wrote:

The vacuum chamber is not actually part of the circuit as I understand it. The actual plasma paths are from each of the cathodes to the anode, which conducts all of the plasma’s current during the axial phase rundown. The anode itself is actually shaped more like a circular Tee flange. I know it looks misleading in the gallery 🙂

Aeronaut, thanks for the response, but what I was asking was more about how the tee flange anode (as you described) manages to stay insulated from the rest of the chamber. Does the pyrex pass completely through the flange, if so how is it sealed to maintain vacuum?

The insulator would have to be roughly the same shape as the anode, JesterX. It probably extends beyond the anode to prevent arcing and minimize inductive losses. My guess is a neoprene or similar gasket. If all else fails, maybe an RTV bead or few ;-P

[Author]

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