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She had diamonds on the soles of her shoes

Posted: Sun Jun 27, 2010 11:40 pm
by John Gallagher
Fast ignition impact fusion with DT methane.
www-pub.iaea.org/MTDC/Meetings/FEC2008/if_p7-30.pdf

Posted: Mon Jun 28, 2010 1:41 am
by MSimon
That is not a working url.

bassackwards

Posted: Mon Jun 28, 2010 3:21 am
by John Gallagher
Make that www-pub.iaea.org/MTCD/Meetings/FEC2008/if_p7-30.pdf darn lisdexia anyways.

Posted: Mon Jun 28, 2010 3:37 am
by D Tibbets
"We found that
a millimeter diamond bullet with the kinetic energy of
1 » 2 MJ, or at the speed of about 1000 km/s, is su±-
cient to initiate a propagating thermal nuclear burn. This
is important, because in 1980s people believe one dimen-
sional compression needs a 50 MJ bullet. This change
can reduce the length of the linear accelerator from 10000
kilometer to less than 100 km."

Mmm, interesting. Only a 100 km long accelerator would be needed. Not exactly a small scale project. How long is the current longest linear accelerator, ~ 3 km?
Dan Tibbets

Posted: Mon Jun 28, 2010 8:58 am
by Skipjack
Yeah and that "diamond bullet" does not sound like an affordable system could ever be built out of that.

Posted: Mon Jun 28, 2010 10:15 am
by MSimon

Re: bassackwards

Posted: Tue Jun 29, 2010 2:42 am
by jsbiff
John Gallagher wrote:Make that www-pub.iaea.org/MTCD/Meetings/FEC2008/if_p7-30.pdf darn lisdexia anyways.
Luckily, copy/paste has never exhibited dyslexia on my computer. Seriously, you *typed* the URL?

Posted: Tue Jun 29, 2010 3:00 am
by DeltaV
Electromagnetically accelerate a superconducting diamond bullet:

viewtopic.php?t=2137

Posted: Tue Jun 29, 2010 8:29 am
by Skipjack
Actually, industrial diamonds are plentify, and cheap.
Uhmm, they are cheapER than gemstone diamonds.
We are talking about tons of fuel that will be needed for a nuclear economy. Using diamonds, real or manufactured for that wont make sense. I am also assuming that making the diamonds takes more energy than a fusion shot using the described method would yield.
It is interesting for experimentation and tests, it wont ever be economic. That is at least what I think.

Posted: Tue Jun 29, 2010 10:34 am
by icarus
It is a type of ballistic confinement fusion, i.e. essentially the same route that the thermonuclear (Hydrogen) bomb achieves fusion. Makes you wonder how small a thermonuclear device using aneutronic fuel (I believe most fusion bombs use not deuterated-hydrogen but Lithium-6) could theoretically be made? The sphericity of the initiating implosion is critical, by all accounts.

Posted: Tue Jun 29, 2010 6:07 pm
by D Tibbets
icarus wrote:It is a type of ballistic confinement fusion, i.e. essentially the same route that the thermonuclear (Hydrogen) bomb achieves fusion. Makes you wonder how small a thermonuclear device using aneutronic fuel (I believe most fusion bombs use not deuterated-hydrogen but Lithium-6) could theoretically be made? The sphericity of the initiating implosion is critical, by all accounts.
Actually, I believe fusion bombs use both tritium and deuterium as that is the easiest reaction. Of course the tritium tends to be provided by insitu production from lithium7 and stray neutrons from the fission trigger, as the shelf life of the tritium is a problem. While sphericity of the implosion is beneficial, it is not always necessary. One of the first two atom bombs was a cannon- target design( I can't remember if it was the uranium or the plutonium bomb). Conversely, I believe that the laser and Z-pinch type implosion fusion approaches spend considerable effort to create good spherical implosions.

Dan Tibbets

Industrial diamond costs

Posted: Wed Jun 30, 2010 12:23 am
by nextbigfuture
http://minerals.usgs.gov/minerals/pubs/ ... omyb03.pdf

Natural and synthetic industrial diamonds differ significantly in price (Boucher, 1997, p. 26.6). Natural industrial diamond normally has a more limited range of values. Its price varies from about $0.30 per carat for bort-size material to about $7 to $10 per carat for most stones, with some larger stones selling for up to $200 per carat.

http://minerals.usgs.gov/minerals/pubs/ ... -diamo.pdf
Total industrial diamond output worldwide was
estimated by the USGS to be about 4.62 billion carats valued
between $1.65 and $2.00 billion.

http://minerals.usgs.gov/minerals/pubs/ ... -diamo.pdf
current price is about $0.16 per carat

Posted: Wed Jun 30, 2010 8:03 am
by Skipjack
And one carat would get you how many KWs of electricity output from such a reactor?

20 KWH for one carat of synthetic diamond

Posted: Tue Jul 06, 2010 7:18 pm
by nextbigfuture
20 Kilowatt hours to produce one carat of synthetic diamond
1 carat is 0.2 grams
100 kilowatthours per gram
100 watthours per milligram

One millimeter of water would be one millionth of a liter.
Diamond is 3.52 grams per cubic centimeter
one millimeter diamond 3.52 milligrams per cubic millimeter
352 watthours per one millimeter diamond
one watt hour is 3600 joules

1.267 megajoules to synthesize millimeter diamond bullet

http://www.stanfordalumni.org/news/maga ... ritty.html


a millimeter diamond bullet with the kinetic energy of 1 » 2 MJ, or at the speed of about 1000 km/s, is su±- cient to initiate a propagating thermal nuclear burn

The neutron energy is ignored in our simulation, but it does help in heating the electrons globally. With simulation obtained shell density and width, about 5% of the 14.1 MeV neutrons will scatter with the ions, and leave approximated one half of their energy to DT ions. The 6 » 7 MeV D or T ions can travel more than 10 times further than 3.5 MeV alpha particles. They can penetrate through the density shell

http://mail.phy.pku.edu.cn/~lei/df/hedip.pdf

The peak energy from an impact is 4 petawatts but mostly at 1.5 petawatts over about 40-50 nanoseconds. 80% of the energy is wasted.

lets say 2 petawatts for 40 nanoseconds
2 million gigawatts for 40 nanoseconds
80 million joules
16 million joules not wasted

3.3 megajoules to produce the millimeter diamond and accelerate it
16 megajoules generated
net 12.7 megajoules per shot.