Just out of interest what did LM have to say for themselves, unless I am misremembering I think you mentioned them being there?
Quote from: Star One on 09/21/2016 06:57 amJust out of interest what did LM have to say for themselves, unless I am misremembering I think you mentioned them being there?That was the US-Japan CT 2016 Workshop on Compact Tori, not the ARPA-E Alpha Meeting.LW is still in relatively early stages of their reactor development. Personally, I am not all that impressed. http://www.physics.uci.edu/US-JAPAN-CT2016/Program_Presentations/2.1_T.McGuire_CT2016.pdfMany other concepts are already much further down the development path and IMHO look a lot more promising including the Princeton FRC, Helions FRC and TAEs FRC. Can you see a pattern there?I am also quite excited about Uri Schumlaks's Flow Z- Pinch, mainly because it could lead to an extremely compact reactor (190 MW with a roughly 1.5 meter tall cylinder of 1.5 meter radius, including shielding) and that has aerospace applications. Plus their device is relative inexpensive. So they can make rapid progress. Scientific validation in less than 3 years.
It is a bit of a bummer that your reactor does not scale up very well. My understanding is that this is mostly due to the restrictions on the thickness of the Scrape Off Layer. Most other fusion reactors scale quite favorably with volume. I do believe that you still have a chance to scale the power output with a higher B. I have read of REBCO HTSC magnets with a magnetic field strength of 25T. Assuming that your reactor also scales with B^4 (like Tokamaks do), there should be quite a potential for making the reactor stronger or smaller in the future. That is of course assuming that things work out as well as you guys hope and the reactor works as predicted. I always tend to get ahead of myself
At this point, we're focused on getting fusion to work at all in an FRC geometry, and our current design is a bit of a balancing act between various physical and technical issues that manifest themselves at larger and smaller machine scales. For instance, if we reduced the radius, our power would have to be reduced substantially in order to keep the neutron wall load low, and we'd need substantially higher magnetic fields as well; on the other hand, if we increased the radius, we'd quickly start running into heating efficiency issues. Basically, once we have a working design, we could then do a bunch of optimization on it and perhaps get refinements to the scaling laws that we're using right now. Getting to that point, of course, is the hard (and, in my opinion, interesting) part!
Quote from: Star One on 09/21/2016 06:57 amJust out of interest what did LM have to say for themselves, unless I am misremembering I think you mentioned them being there?I am also quite excited about Uri Schumlaks's Flow Z- Pinch, mainly because it could lead to an extremely compact reactor (190 MW with a roughly 1.5 meter tall cylinder of 1.5 meter radius, including shielding) and that has aerospace applications. Plus their device is relative inexpensive. So they can make rapid progress. Scientific validation in less than 3 years.
Z pinch could be used as an electric thruster even without fusion. Plus the jet flow frontend = chemical/thermal - electric - fusion Tri-mode.
To solve the problem, researchers examined something called "plasmoid instability," which causes two-dimensional magnetic sheets to thin down into smaller "islands." Once a sheet has broken down to a certain point, "the plasmoid instability occurs on a short time scale, leading to explosive growth of the plasmoids," according to the paper. That causes the fields to reform in a different orientation, causing solar flares and other phenomena.The researchers still aren't sure why the plasma breaks down into islands, as that seems to defy the "power laws" of physics. Nevertheless, the work could help scientists better predict solar flares, erratic gamma ray blasts and other violent activities. Perhaps most importantly, it could lead to a better understanding of the magnetic fields caused by plasma inside Tokamak fusion reactors. If they can figure that out, we can solve pretty much all of our energy problems.
HTSC tapes are one of the main reasons I look forward to DEMO. They really change the picture of the sort of scale you need to achieve viable fusion power. Great to see them working into this role as well!
Quote from: Rei on 04/03/2017 07:43 amHTSC tapes are one of the main reasons I look forward to DEMO. They really change the picture of the sort of scale you need to achieve viable fusion power. Great to see them working into this role as well!I think SPARC and ARC will happen long before DEMO (unless they never get funding). They are really amazingly compact for tokamaks. PPPLs system is even more compact, though.
Quote from: Elmar Moelzer on 04/03/2017 07:53 amQuote from: Rei on 04/03/2017 07:43 amHTSC tapes are one of the main reasons I look forward to DEMO. They really change the picture of the sort of scale you need to achieve viable fusion power. Great to see them working into this role as well!I think SPARC and ARC will happen long before DEMO (unless they never get funding). They are really amazingly compact for tokamaks. PPPLs system is even more compact, though.Aren't ARC and SPARC just unfunded design concepts? ITER starts plasma experiments in 2020; I doubt ARC could come online before that, and they're testing the same basic sorts of operational issues. I can't imagine them abandoning ITER and starting over with ARC. And SPARC very well could be what DEMO ends up like. Conceptual design on DEMO isn't due for years.I guess it depends what entity is funding it.
Aren't ARC and SPARC just unfunded design concepts? ITER starts plasma experiments in 2020
Quote from: Rei on 04/03/2017 09:29 pmAren't ARC and SPARC just unfunded design concepts? ITER starts plasma experiments in 2020ITER first plasma has been delayed to 2025.
Quote from: Elmar Moelzer on 04/04/2017 12:37 amQuote from: Rei on 04/03/2017 09:29 pmAren't ARC and SPARC just unfunded design concepts? ITER starts plasma experiments in 2020ITER first plasma has been delayed to 2025.Wow, missed that. That's... unfortunate. :Þ