[ExI] lockheed's fusion video

[John Clark]

On Tue, Oct 21, 2014 at 2:37 PM, spike <spike66 at att.net> wrote:

> All of those thermal neutrons must be absorbed somehow,


The neutrons produced from a fusion reaction are not thermal neutrons, they
are very very high speed neutrons, faster even than the neutrons produced
in a fission bomb. Before super fast neutrons can be absorbed by anything
they must be slowed down, water can do that, and so can graphite. Once the
neutrons have slowed down to thermal speed there are a number of materials,
Boron for example, that can absorb them. Or you can use one material that
can do both jobs like Lithium 6, first it slows the very fast neutrons down
(and gets hot as a result) and then it can react with the slow neutrons and
produces Tritium which you then extract and feed back into the reactor.

 > We can assume a best case (known) for material to absorb neutrons, lead,
>

Lead is good at stopping X rays and Gamma rays but it's not so good at
stopping neutrons, you'd do much better with jugs of water with some 20
Mule Team Borax dissolved it it, the water would slow the neutrons down and
then the Boron can absorb them.


> > Whatever is that material, which is not lead, still absorbs some of the
> neutrons and it still gets neutron rich, which causes it to break down by
> fission eventually.
>

All nuclear reactions, fission or fusion, that humans have ever used to
make energy also produce neutrons, although some reactions we haven't used
do not. A neutron flux can damage a solid by knocking atoms out of place
and physically weakening the material. Some exotic and expensive metals
such as Hastelloy-N are resistant (although not immune) to neutron damage,
it's a alloy of nickel, molybdenum, chromium, cobalt, iron, copper,
manganese, titanium, zirconium, aluminum, carbon, and tungsten. Also to
some degree the neutron damage a metal receives can be repaired by
annealing, heating the metal to a high temperature and then cooling it
rapidly. Neutron damage is a more serious problem in magnetic confinement
fusion than it is in inertial confinement fusion because the most expensive
parts (Lasers or particle accelerators) are further away from the fusion
reaction.

In conventional fission reactors the mechanical damage caused by neutrons
to the Uranium fuel rods is a major problem, that's why the rods have to be
removed and replaced by new rods long before all the U235 in them has been
used up, a expensive and wasteful and time consuming process.  Liquid
Fluoride Thorium Reactors don't have that problem because its fuel is in
liquid form.

Not all fusion reactions produce neutrons. The fusion reaction between non
radioactive deuterium (Hydrogen 2) and non radioactive Helium 3 produces
non radioactive Helium 4, an easily controlled proton, 18.3 mev of energy,
and most important of all, no neutrons. Unfortunately you need a higher
temperature to achieve it than the deuterium tritium reaction most are
talking about. Also, there is not much Helium 3 on the Earth, although
there is
probably a lot of it that could be mined on comets and on the ice moons of
the outer planets. A Boron Hydrogen reaction also produces no neutrons but
it needs a even higher temperature.


>  > But hey, I am not a nuclear physicist, so perhaps he has found
> something astonishing that the old timers missed.  I am not buying stock.
>

I'm not buying the stock either and I hope that in 10 years I'll be kicking
myself that I hadn't.

  John K Clark
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