Fusion Message Board

In this space, visitors are invited to post any comments, questions, or skeptical observations about Philo T. Farnsworth's contributions to the field of Nuclear Fusion research.

Subject: Re: Secondary Neutrons
Date: May 26, 6:18 pm
Poster: Jim Lux

On May 26, 6:18 pm, Jim Lux wrote:

>>Fusioneers are out for clean fusion only. To sully the beauty of the fusion process with a dirty, fission based, hybrid, hanger-on process is blasphemous. Farnsworth would has called us out into the alley for fisticuffs on this one!! Long term, and with big systems, we would be makin' more nuclear waste along with fissile material!!!! Sort of a fusion-fission breeder.

Leaving aside the problems of neutron activation of the wall of your fusor, tritium production, and all the other rad waste problems, eh?


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>1. Even a rip roarin', hot fusor of 10e6 neuts/sec if surrounded with a U-238 blanket would not be have a big flux working the Uranium.


>2. A natural thought is to make the inner grid construction out of U-238 and that is the best of the lot. Here, it would be in an intense field of FAST neutrons

U isn't particularly refractory element.. MP is about 1100 C, you'd probably wind up melting it.
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>3. The really big problem is that the U-238 fission bit is best accomplished with THERMAL or SLOW neutrons.

And I suppose that getting a bunch of U235 or Pu239, which will fission with fast neuts is a bit of a problem and might raise some regulatory eyebrows???

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>So, this idea kinda' looks grim with amateur fusor output levels. Nonetheless, it appears neato on the surface and shows we are thinkin'.

Just trying to think of something interesting to do with those neutrons. You've already paved the way to just making them in the first place (which is no easy feat).

But what I really wanted to do was breed Pu.. Let's see, how long will it take to make a kilo of Pu with 1E6 neutrons/sec? Only 2.5E18 seconds... or 80,000 yrs... with half life of 24k yrs, I don't know that you could even keep ahead of it, even if the cross section were infinite.