WB-6 as example of the safety of polywell

If polywell fusion is developed, in what ways will the world change for better or worse? Discuss.

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WB-6 as example of the safety of polywell

Post by jsbiff »

One of the biggest initial problems for any fusion reactor design, will be public concern about the safety of a fusion reactor. They will probably, initially, think that fusion is like fission - dangerous, radioactive, risk of meltdown or explosion.

I remember when I first read about WB-6, and how there was a short in the reactor and it vaporized itself, my first reaction was, "Great, there's a ringing endorsement for safety - one of the prototypes blew up!"

But then I thought about it some more. One of the prototypes blew up - and it was no big deal. No one got hurt, there wasn't a big radiation leak that got on the evening news, the scientists working with it weren't exposed to dangerous levels of radiation (granted, the prototype was fairly small).

But, all in all, I think if there is any public worry/political resistance to PW fusion (if it works out, of course), everyone trying to promote the PW should point out the example of the explosion of the WB-6 and how it was no problem.

Heck, maybe EMC2, in conjunction with the DoE or someone, should at some point *purposely* blow up an operating commercial-scale PW reactor (like, maybe WB-D once they've gotten enough info out of operating it to show its viability and improve the design, etc), with the press invited to cover it, to demonstrate the safety to the public?

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Post by KitemanSA »

You can't "blow up" a Polywell Reactor. All you can do is short the coils, which is similar to "blowing up" a transformer. With SC coils, that can be a significant electrical event.

But no matter how it happens, lots of sparks and ozone, but no nuclear content.

If you are using DT fuel (why?!?!) you would release whatever the current fuel load of T. Quite small IIRC.

D Tibbets
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Post by D Tibbets »

I have not seen any pictures of WB6 after it shorted out. The rhetoric probably distorted the picture. I don't think the machine Blew up per say. Think of a high voltage transformer. When they short out they can create impressive electrical displays, and can even heat up the oil they are in and create an explosion. This would be a worse case scenario for a Polywell short (except see below). The major difference is that the Polywell magrid is in a vacuum chamber, so any blast (over pressure) effects would be much less. A portion of the magnet casing may melt and sputter some. That is all. While that would be devistating for the magnet casing and possibly other structures within the vacuum chamber, I would not expect anything would be noticed outside the chamber other than possibly a dull thump.

Super conducting magnets is another matter. They can hold an tremendous amount of electrical energy. If they lose coolent, they can very quickly dump all of this energy into surrounding structures, dwarfing the effects mentioned above. The amount of energy stored in a superconducting magnet is dependent on several factors. I suspect that such a accident would result in an explosion similar to what happend to the LHC in 2008. The vacuum casing was ruptured and knocked off its pedistal. Such an accident would be confined within any reasonable room. This could damage steam lines though, and subsequent damage could be exaggerated. Perhaps something similar to when old steam locomotives blew up. . As far as neuclear expolsions- forget it. There might be some concern about scattering radioactive transmutted structureal material , but even a modest containment building would contain it.

A Tokamak has even stronger (probably) and much larger superconducting magnets (plus they are in air, not within an enclosing strong vacuum chamber), and if they failed suddenly, they could result in a substantially larger explosion. There are safty measures that could be taken, but with multiple failures this scenario needs to be planned for.

Dan Tibbets
To error is human... and I'm very human.

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