Lockheed SkunkWorks Fusion plan

[jimgraber]

In the news today, several articles about Lockheed's ambitious five or ten year plan. eg this one from the Washington Post. http://www.washingtonpost.com/news/...in-a-decade-lockheed-martin-is-betting-on-it/ This one from Aviation Week
http://aviationweek.com/technology/skunk-works-reveals-compact-fusion-reactor-details
gives the most details that I have found so far.
It is described as a new design based on many old designs, but to the extent that I understand it, it seems to most closely resemble the old mirror-machine design.
Any more knowledgeable comments? TIA jimgraber

 

[dipole]

They posted this on their website today, apparently trying to generate some press.

http://www.lockheedmartin.com/us/products/compact-fusion.html

Seems like they want investors to help out. I remain skeptical - they don't really say what about their concept is new from other magnetic confinement concepts.

 

[mheslep]

Good luck to them. I'm happy to see some alternatives to the half-century long projects like ITER and NIF, however I think that if Lockheed Martin has not already demonstrated a significant Lawson criterion advance in the lab, today, then they have no hope of building a net power reactor within five years. The statement on that website is nebulous; could mean anything: "...will be able to develop a prototype within the same five year timespan." A prototype of what? Net power? Some neutron count X far below net power? Would it breed its own tritium?

Also, LM touts the small size of their design as a feature, an advantage making the like of fusion powered space and aircraft possible. Given fission releases only ~1% of its energy via neutrons, and D-T fusion ~80% via faster neutrons, attempting to go small and thus raise the neutron density on the wall, a solid wall, seems ill considered.

 

[mheslep]

BTW, Thomas McGuire, the researcher featured in the promo video wrote his Phd dissertation on improvement on ye olde electrostatic fusors.
"Improved Lifetimes and Synchronization Behavior in Multi-grid Inertial Electrostatic Confinement Fusion Devices"
http://ssl.mit.edu/publications/theses/PhD-2007-McGuireThomas.pdf

 

[the_wolfman]

It is described as a new design based on many old designs, but to the extent that I understand it, it seems to most closely resemble the old mirror-machine design.

Actually, the article is very vague about the design. (It is Skunkworks after all). They describe it as a hodgepodge of several different concepts, but its not clear how you combine these concepts into one concept. The artistic drawing of the experiment isn't too helpful either, and it doesn't seem to match the picture (count the superconducting coils).

The vocabulary that they use to describe the reactor implies something different. The term compact has a very specific meaning in the fusion community. It does not mean "small." Instead it refers to a toroidal plasma that is confined in cylindrical shell (spheromaks and Field Reversed Configurations). Mirrors are not normally called compact because the plasma is not toroidal. Tokamaks are not compact because they are confined in toroidal shells. By calling their device compact, they seem to be implying that its either a spheromak or a FRC. The descriptor high-beta would be consistent with an FRC which can have engineering betas of ~100%. Yet they make no mention of FRCs in any of the articles.

I could go on, but hopefully you get the idea. Skunkworks it notorious about being very secretive about their work, and these articles are no different. With out knowing what their concepts is, its difficult to provide any meaningful analysis. To say anything more than that is purely speculation.

 

[jimgraber]

I am not even sure if their device is intended to run pulsed or steady state. Their steam turbine output suggests steady state, but their high beta claim suggests compression and possibly pulsed output to me. The Aviation Week (AW) article shows a cylindrical schematic which resembles a very primitive mirror machine. The AW movie shows a small completed spherical system, which could be a spheromak or a fusor, and a much larger cylindrical device still under construction. I see very little in the way of coils in the movie. I will watch it again later and look for coils. Real life is about to intervene for a few more hours, so I may not reply soon and cannot review the movie again until lunch or later.

 

[jimgraber]

http://news.sciencemag.org/physics/2014/10/are-old-secrets-behind-lockheeds-new-fusion-machine
The above new link suggests (or speculates) that it is an FRC in a Picket Fence, also called a cusp. Supposedly the Cusp was too leaky, and the FRC was too short-lived. Maybe the combination might work?

 

[nsaspook]

http://www.google.com/patents/US20140301518

 

[jimgraber]

That patent is a really great find, if one is interested in the details.

 

[Hercuflea]

Congratulations, Lockheed, you read a book about magnetic mirrors. Too bad they don't work...

 

[mheslep]

Any comment on the specifics of mirror short-comings, that would then shed light on whether Lockheed is at least attempting to improve on them?

 

[jimgraber]

First, the design apparently combines at least some aspects of a cusp and some aspects of a mirror. To me, it looks more like a cusp in a mirror, but I could be wrong. This indicates one major attempt to make an improvement.

Second, both the cusp and the mirror have "open field lines" and are thus "much too leaky", at least according to critics.

Third, if you google around, you will find a fair amount of polite, but definite, skepticism from experts and mainstream researchers.

Finally, I am not an expert, so check out everything I say with more knowledgeable sources.Jim Graber

 

[mheslep]

First, the design apparently combines at least some aspects of a cusp and some aspects of a mirror. To me, it looks more like a cusp in a mirror, but I could be wrong. This indicates one major attempt to make an improvement.

The two are a combination, and *different* from prior efforts. Difference alone without rationale does not indicate improvement, not even an attempt.

Third, if you google around, you will find a fair amount of polite, but definite, skepticism from experts and mainstream researchers.

Yes and have appeared here too, but I've not seen any specifics, or references to prior specifics.

 

[etudiant]

The impression is that the main improvement here is the willingness to eat the elephant one bite at a time, rather than to attempt a single hugely expensive solution such as ITER or even the NIF. The concern is that this wide ranging approach may be inadequate when the starting performance falls short by several orders of magnitude. Still, I think the US fusion effort suffered disproportionately from the decision to focus the limited resources on just a couple of approaches, simply because the field was not well enough understood to make those determinations. So I applaud Lockheed's initiative and wish them well. They have the right idea.