Would it be possible to build a model tokamak

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Discussion Overview

The discussion revolves around the feasibility of creating a model tokamak or a demonstration of swirling plasma in a tube, inspired by fictional representations like the arc reactor from Iron Man. Participants explore the concept of demonstrating plasma behavior without achieving fusion, focusing on the technical and regulatory challenges involved.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Homework-related

Main Points Raised

  • Some participants propose creating a swirling plasma in an acrylic tube as a demonstration of plasma behavior, without the intention of achieving fusion.
  • Others mention that while it is possible to ionize gases in tubes to create plasma, achieving the necessary conditions for fusion is not trivial and involves significant regulatory considerations.
  • A participant notes that the easiest fusion reactions, such as d+t and d+d, produce neutrons that require special safety measures.
  • There is a discussion about the legal restrictions on building devices that could produce radiation, with references to federal regulations governing nuclear materials.
  • Some participants express interest in using ring magnets to illustrate how plasmas respond to magnetic fields in a small apparatus.
  • Concerns are raised about the duration of plasma discharges in tokamaks, with smaller experiments typically having very short discharge times that may not be suitable for visual demonstrations.

Areas of Agreement / Disagreement

Participants generally agree on the idea of demonstrating plasma behavior without fusion but have differing views on the feasibility and safety regulations associated with building such a demonstration apparatus. The discussion remains unresolved regarding the specifics of regulatory compliance and the practicalities of constructing a model.

Contextual Notes

Participants mention the need to comply with federal and state laws regarding radiation and nuclear materials, but specific legal texts or guidelines are not provided. There is also uncertainty about the exact nature of the demonstration and the technical challenges involved.

Who May Find This Useful

This discussion may be useful for students or hobbyists interested in plasma physics, regulatory aspects of experimental physics, and the practical challenges of building demonstration models in a safe and compliant manner.

Warpspeed13
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Would it be possible to just get a swirling plasma in an acrylic tube kind of like the arc reactor in iron man? I'm not talking about anything close to the temperatures or pressures required for fusion just kind of a demo piece to show the general idea.
 
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Warpspeed13 said:
Would it be possible to just get a swirling plasma in an acrylic tube kind of like the arc reactor in iron man? I'm not talking about anything close to the temperatures or pressures required for fusion just kind of a demo piece to show the general idea.
One can buy glass tubes filled with gases, e.g., hydrogen, for electrical discharges, i.e., like fluorescent tubes. One passes a current through the tube at sufficiently high voltage to ionize or excite the gas and obtains an emission spectrum.

See the lamp demonstrated here -
http://hyperphysics.phy-astr.gsu.edu/hbase/hyde.html#c4

One would need to heat the gas to high temperatures to get much of a plasma - a completely dissociated gas in the form of nuclei and free electrons.

It however would not demonstrate fusion.

The easiest reactions for fusion are the d+t and d+d reaction. d+t fusion produces a 14.1 MeV neutron, and the d+d reaction generates a 2.45 MeV neutron in about 50% of the reactions, so that requires special protection.

Building a tokamak is not a trivial undertaking, and is restricted under federal and state laws governing the production of radiation sources.
 
Ya I just wanted to demonstrate how the gasses swirled and the basic concept not generate fusion energy. Also where can you find those laws I tried googling it for a school report a while back and couldn't find anything approaching an official set of rules.
 
We'll other than the basics of no radioactive materials over x amount and refining / possessing u-235/Pu-239 is a big no no
 
Federal Laws pertaining to radiation and nuclear materials can be found in Chapter 10 of the Code of Federal Regulations (10 CFR).

http://www.nrc.gov/about-nrc/regulatory/rulemaking/potential-rulemaking/opt-revise/faqs.html

Regulation of nuclear materials.
http://www.nrc.gov/about-nrc/radiation/protects-you/reg-matls.html

High voltage devices produce UV and X-ray, in addition to visible light, so there may be state as well as federal regulations. It is one's responsibility to comply with all relevant state and federal laws.
 
Cool thanks
 
Warpspeed13 said:
Ya I just wanted to demonstrate how the gasses swirled and the basic concept not generate fusion energy. Also where can you find those laws I tried googling it for a school report a while back and couldn't find anything approaching an official set of rules.

What do you mean by "swirled?"

I think you are interested in building a small apparatus to demonstrate how plasmas respond to magnetic fields and perhaps illustrate some basic concepts related to magnetic confinement.

You can create a plasma in small cylindrical acrylic tube and use ring magnets to study the response.

You certainly don't want to build a tokamak. Only the largest tokamaks have discharges that last for seconds. Most smaller experiments have discharges that last only a few milliseconds (if that). Its too short of a time for visual demonstration.
 
Yep that's exactly what I was talking about
 

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