New approach to stabilize fusion plasmas

Buzz Bloom

Gold Member
1,991
327
It's is a bit early to make a final decision for 2019's most important scientific discovery, but for now this gets my vote.
 
151
119
This isn't my field, but I like learning about fusion progress. I've got a few questions about what they're saying here. Would someone be kind enough to explain?
https://phys.org/news/2019-01-scientists-stabilizes-fusion-plasmas.html said:
The physical mechanism that PPPL has identified works like this:

  • The temperature perturbations affect the strength of the current drive and the amount of RF power deposited in the islands.
  • The perturbations and their impact on the deposition of power feedback against each other in a complex—or nonlinear—manner.
  • When the feedback combines with the sensitivity of the current drive to temperature perturbations, the efficiency of the stabilization process increases.
  • Furthermore, the improved stabilization is less to likely to be affected by misaligned current drives that fail to hit the center of the island.
What I got out of this--please correct me if I am wrong--is that cooler regions in the plasma have a naturally higher electrical resistance. When they form the current driven through the plasma, to reach and maintain fusion temperatures, avoids them (taking the path of least resistance) and they cool more. But these cooler regions also happen to be more receptive to RF power, which they absorb, causing their temperature to rise and correcting the instability.

Am I on the right track here, or completely misunderstanding this? Thank you.
 

Tom.G

Science Advisor
2,544
1,368
What I got out of this--please correct me if I am wrong--is that cooler regions in the plasma have a naturally higher electrical resistance. When they form the current driven through the plasma, to reach and maintain fusion temperatures, avoids them (taking the path of least resistance) and they cool more. But these cooler regions also happen to be more receptive to RF power, which they absorb, causing their temperature to rise and correcting the instability.
It seems to be something like that. A 'better' (but still not real clear) definition can be found (especially in the last 2 paragraphs) at:
https://phys.org/news/2018-08-higher-plasma-densities-efficient-tokamaks.html

The word choices in both articles makes it hard for us non-specialists to find the actual intent of what is being said.

Cheers,
Tom

p.s. more can be found if you drill down thru the link at the end of each phys.org article. the link I mentioned here was four or five deep from the original post in this thread.
 

Want to reply to this thread?

"New approach to stabilize fusion plasmas" You must log in or register to reply here.

Physics Forums Values

We Value Quality
• Topics based on mainstream science
• Proper English grammar and spelling
We Value Civility
• Positive and compassionate attitudes
• Patience while debating
We Value Productivity
• Disciplined to remain on-topic
• Recognition of own weaknesses
• Solo and co-op problem solving
Top