General Fusion in the news

[Skipjack]

Well, charging 7500 USD per seat sure seems to be one way to finance their operation

[choff]

Actually $7,500.00 Canadian for the whole TED show, so a bit less than in USD, but that includes everything, not just GF.

[mvanwink5]

It is just a social event for politically correct people with lots of money. Did you read where Laberge was working on getting his Steve Jobs presentation skills honed and the talk dumbed down so a 5th grader would kind of understand it? I am not sure any of you guys would fit in anyway.
Yes, yes, I'm being a bit snarky.

[ladajo]

The average bear certainly does not have $7500 bucks to toss at attending TED. Makes you wonder who really goes and what the friggin point actually is.

To put it in perspective, $7500 bucks is half the average annual cost for a student at a public school around these parts.

Sadly ridiculous. I will vote with my feet and ignore TED from now on.

[hanelyp]

The impression I've gotten of Ted Talks is long on enthusiasm, short on technical meat, a place for to see and be seen while the audience pretends to be tech savvy.

[asdfuogh]

I thought the point of the TED talks was to induce enthusiasm in potential investors. You talk about the thing you're doing, and basically sell yourself and your product. Interested investors can then contact you afterwards.. no?

[mvanwink5]

The impression I've gotten of Ted Talks is long on enthusiasm, short on technical meat, a place for to see and be seen while the audience pretends to be tech savvy.

Like an infomercial you pay $7500 a seat to go see.

[mvanwink5]

Here is a blog article on GF:
http://wavewatching.net/2013/12/30/here ... ment-81425
In the blog comments Nathan Gilliland posted a comment with a twitter link.

Also, here is link to GF's paper found on the blog, "Fluid-Structure Interaction Simulations in Liquid-Lead
Simulations of the General Fusion Magnetized Target Fusion Reactor Concept"
It is fascinating.
http://www.cs.ubc.ca/~jgregson/images/J ... Thesis.pdf

[mvanwink5]

GF's critical issue with achieving effective net fusion breakthrough is stable spheromak compression. As I mentioned before, last year GF found a stable spheromak shape and was pursuing testing and scale up program. For background, here are some earlier papers relating to their plasma injector development.

http://www.generalfusion.com/downloads/ICC2008_SJH.pdf
Development of Merged Compact Toroids for Use as a Magnetized Target Fusion Plasma

http://www.generalfusion.com/downloads/ ... ion_detail
An Acoustically Driven Magnetized Target Fusion Reactor

http://www.generalfusion.com/downloads/ICC2008_MGL.pdf
Experimental Results for an Acoustic Driver for MTF

http://www.cs.ubc.ca/~jgregson/images/J ... Thesis.pdf
Fluid-Structure Interaction Simulations in Liquid-Lead

http://plasma.physics.swarthmore.edu/br ... nJFE08.pdf
Flow Dynamics and Plasma Heating of Spheromaks in SSX

http://plasma.physics.swarthmore.edu/br ... sGRL05.pdf
Fluid and kinetic structure of magnetic merging in the Swarthmore Spheromak Experiment

[asdfuogh]

Yep. From what I was told, they have done the initial testings with their 18 piston proto-type and that's all fine and dandy (and simulations indicate that the 180 piston version will be more uniform). What they are having trouble with is stability, but the nice thing is that there are other research teams who are also working on similar compact toroids so they can always (well, somewhat) draw from each other.

[mvanwink5]

asdfuogh, "but the nice thing is that there are other research teams who are also working on similar compact toroids." That was my thought too, however, what I was thinking was all the guys compressing spheromaks (GF, Tri-Alpha, Helion, Solox) sink together or float together on this issue. It did occur to me that GF might have a lower compression hurdle than Helion or Tri-Alpha as GF is going for D-T, not PBJ, but maybe I am wrong on that. It also made me wonder if GF's use of the chalice shaped spheromak was a common approach. Maybe we will learn something about test status from TED Tuesday.

Anybody have access to the live TED webcast through work or a university link (costs big buckeroos). Or maybe we'll just have to wait... seems we have lots of practice doing that.

[Skipjack]

asdfuogh, "but the nice thing is that there are other research teams who are also working on similar compact toroids." That was my thought too, however, what I was thinking was all the guys compressing spheromaks (GF, Tri-Alpha, Helion, Solox) sink together or float together on this issue. It did occur to me that GF might have a lower compression hurdle than Helion or Tri-Alpha as GF is going for D-T, not PBJ, but maybe I am wrong on that. It also made me wonder if GF's use of the chalice shaped spheromak was a common approach.

Helion is doing TD also.

[asdfuogh]

It's not just the private companies you mentioned. There were also university and national lab research teams that worked on spheromaks, FRCs, and other compact toroids. I think two of the main ones have lost funding in the last couple of years (ie. University of Washington's Redmond lab.. which spawned Helion, I believe, and Los Alamos's FRC-based MTF device). There are still universities that work on FRC experiments (because of magnetic reconnection and propulsion) and FRC/spheromak/CT simulations (because they're quite similar to tokamak geometry, but with q~0).

>Helion is doing TD also.

It's great for attracting investors, but doing D-T might cost more / take even more time because you have to figure in the cost in money and time to replace/protect the device. D: If only investors (both private and government) weren't so idiotically focused on super short term results.

[crowberry]

GF's critical issue with achieving effective net fusion breakthrough is stable spheromak compression. As I mentioned before, last year GF found a stable spheromak shape and was pursuing testing and scale up program. For background, here are some earlier papers relating to their plasma injector development.

GF also wants to heat the spheromak to 500 eV before injection. Looking at the FPA December presentation on page 13 it is shown that they have reached 200 eV, while they would want to reach 500 eV and expect actually to exceed 600 eV.

The Richtmeyer-Meshkov instability can be a problem too, see the FPA presentation on page 6 and the following two papers.
If there is too much lead contamination in the plasma then it will cool off. There are several things that GF can adjust to keep the problems under control like the acoustic pulse amplitude, duration, the angular velocity of the PbLi-fluid, possible injection of Li-nearest the center of the reactor to avoid Pb-contamination. Also the temperature and density of the plasma before the acoustic compression are important parameters. To have an idea of the good parameter set realistic simulations are needed. Currently the GF simulations are simplified and are missing important aspects of the acoustic vortex compression.

On The Collapse of a Gas Cavity by an Imploding Molten Lead Shell and Richtmyer-Meshkov Instability
http://www.sinmec.ufsc.br/~dihlmann/MAL ... Froese.pdf

This is behind a paywall. I think it is a slightly more recent version of the previous paper.
Richtmyer–Meshkov instability of a liquid–gas interface driven by a cylindrical imploding pressure wave
http://www.sciencedirect.com/science/ar ... 3013004143

This is a paper about the instrumentation GF uses to measure the properties of the plasma. This is also behind a paywall.
High-bandwidth polarimeter for a high density, accelerated spheromak
http://scitation.aip.org/content/aip/jo ... /1.4819307

This presentation is similar to the FPA December presentation, but it has some additional interesting material
Progress Towards Acoustic Magnetized Target Fusion: An Update on the R&D Program at General Fusion
http://www.cns-snc.ca/media/uploads/GF_ ... _06_06.pdf

[Skipjack]

It's not just the private companies you mentioned. There were also university and national lab research teams that worked on spheromaks, FRCs, and other compact toroids. I think two of the main ones have lost funding in the last couple of years (ie. University of Washington's Redmond lab.. which spawned Helion, I believe, and Los Alamos's FRC-based MTF device). There are still universities that work on FRC experiments (because of magnetic reconnection and propulsion) and FRC/spheromak/CT simulations (because they're quite similar to tokamak geometry, but with q~0).

From what I know, it was James Grossnickle's FRC lab that was closed. He was working on a steady state FRC device. Helion is a spin off of MSNW LLC which is still alive and kicking (they just updated their prototype hardware). John Slough, the president of MSNW is still working as a professor at the University of Washington. So his lab was (to the best of my knowledge) not closed.

Helion is doing TD also.

It's great for attracting investors, but doing D-T might cost more / take even more time because you have to figure in the cost in money and time to replace/protect the device. D: If only investors (both private and government) weren't so idiotically focused on super short term results.

Helions device is NOT a tokamak. Many of the problems DT burning toks have do not apply to Helions colliding beam reactor. First of all, the device is a lot smaller and more compact. The material issues are much less dramatic since the burn chamber is physically separated from the expensive parts of the reactor. The burn chamber is only a small part of the device. It is a simple short cylinder which is easier to cover with a blanket of liquid lithium than the toroidal shape of tokamak. This also makes it much easier to extract energy from it and to replace it should the material wear to much during long time operation.