[FRIAM] technical notes on fusion announcement

[glen]

Excellent! Thanks. I think I'll have to push this topic for another day. I've got a few more links from other fora I'll plop here just in case I only land back here if/when I pop it off the stack later:

https://lasers.llnl.gov/news/magnetized-targets-boost-nif-implosion-performance
https://spie.org/news/nuclear-fusion-nifs-hall-of-mirrors-may-solve-worlds-energy-crisis?SSO=1
https://www.science.org/content/article/fusion-power-may-run-fuel-even-gets-started
https://arstechnica.com/science/2022/12/what-enabled-the-big-boost-in-fusion-energy-announced-this-week/

On 12/13/22 16:23, Steve Smith wrote:
> I think DT refers simply to the remaining fraction of Deuterium/Tritium remaining after the reaction event (-4%) without specific accounting for remaining D vs T.
> 
> My understanding is that D-T  fusion occurs at a lower temperature than D-D but that once fusion commences (starting with D-T), both D-T and D-D reactions occurring in similar amounts. In laser-driven ICF (as with NIF) I believe the ratio of D/T is nominally 50/50 though it would seem to make sense to have a higher T to D ratio but most references I see imply equal portions.   An equal number of D-D and D-T reactions would seem to consume D more quickly, though as that commences, the D/T ratio would go down, making D-T reactions (yet) more likely...   tricky business, no wonder it has taken decades to get to this point?
> 
> The Wikipedia Entry on ICF is pretty good: https://en.wikipedia.org/wiki/Inertial_confinement_fusion
> 
> I found several popular science Articles which seem to reinforce my sense that this "breakthrough" is not as significant as implied:
> 
>     https://www.science.org/content/article/fusion-breakthrough-nif-uh-not-really
> 
> Other interesting/relevant links regarding D-T and D-D fusion...
> 
> https://www.researchgate.net/publication/263507001_Species_separation_and_modification_of_neutron_diagnostics_in_inertial-confinement_fusion/figures?lo=1
> 
> https://www.energy.gov/science/doe-explainsnuclear-fusion-reactions <https://www.energy.gov/science/doe-explainsnuclear-fusion-reactions>
> 
> https://science.jrank.org/pages/4732/Nuclear-Fusion-D-D-D-T-reactions.html <https://science.jrank.org/pages/4732/Nuclear-Fusion-D-D-D-T-reactions.html>
> 
> On 12/13/22 4:36 PM, glen wrote:
>> That's why I asked. I guess I'll assume DT means both deuterium and tritium, not just deuterium. If you were going to track fuel use, you'd track the rarer part more closely, right?
>>
>> On 12/13/22 09:22, Frank Wimberly wrote:
>>> DT = deuterium?
>>>
>>> ---
>>> Frank C. Wimberly
>>> 140 Calle Ojo Feliz,
>>> Santa Fe, NM 87505
>>>
>>> 505 670-9918
>>> Santa Fe, NM
>>>
>>> On Tue, Dec 13, 2022, 10:21 AM glen <gepropella at gmail.com <mailto:gepropella at gmail.com>> wrote:
>>>
>>>     Awesome. Thanks. I'm still trying to catch up with the QC Wormhole kerfuffle. Who knew Quanta was so click baity?
>>>
>>>     What is "DT"?
>>>
>>>     On 12/13/22 09:02, Marcus Daniels wrote:
>>>      > In case no one wanted to get up at 7:00am to watch DOE administrators talk:
>>>      >
>>>      >
>>>      > 1. Controlling the laser in space and time was important for maintaining symmetry.  Timing precision of 25e-12 secs and laser spatial precision of 5e-12 meter were needed. This was thought to be the main explanation for the achievement.
>>>      >
>>>      > 2. 8% more power on the laser this time
>>>      >
>>>      > 3. x-ray tomography is used to find flaws in the capsules.  Developing software to do the counting.
>>>      >
>>>      > 4. They have ongoing efforts to study the fabrication systems and their components (done in Germany) to find idiosyncrasies of each.
>>>      >
>>>      > 5. Laser technology improvements since NIF was built which are 20% more efficient.
>>>      >
>>>      > 6. Target cost is from labor, and it takes 7 months each
>>>      >
>>>      > 7. 4% of DT is burned in a shot
>>>      >
>>>      > 8. Machine learning ties together radiation hydrodynamics and experimental data.   (It sounded preliminary.)
>>>      >
>>>      > 9. The (successful) capsule had more defects than previous experiments.   However, previous experiments did show benefits from capsule quality.
>>>      >
>>>      > 10. 15% of experiments are indirect drive of this kind, 15% of experiments are other approaches to ignition.  The rest are weapons and materials characterization.
>>>      >
>>>      > 11. Anomalous laser directional control were problems in the summer runs.   Fixed that.


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