Re: fission question

From: Steven Sharp (sharp_at_cadence.com)
Date: 07/26/04 

Date: 26 Jul 2004 15:29:55 -0700

puppet_sock@hotmail.com wrote in message news:<c7976c46.0407260611.62276699@posting.google.com>...
>
> Horseback feeling from experience with commercial nuclear fuel:
> A core such as this, in five seconds, would be fairly accurately
> treated as adiabatic.

Certainly the models in the Los Alamos report assumed this.

> I'm thinking, though, that a significant fraction of the energy
> would have gone away as neutrons that didn't interact with the
> core.

With plutonium, you get 2 spare neutrons from each fission. A typical
fission neutron has around 2 MeV. Fission releases around 180 MeV.
So only around 2% of the fission energy could be carried away by neutrons.

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