First 3D Simulations of Complete Nuclear Detonations

jhiv writes: "The National Nuclear Security Administration (NNSA) reports that 'Los Alamos and Lawrence Livermore national laboratories have completed the first full-system three-dimensional simulations of a nuclear weapon's explosion'. The simulations are two of the largest computer simulations ever attempted, each taking weeks to complete on the ASCI White supercomputer. The Los Alamos team used the ASCI Blue Mountain supercomputer to visualize the results. Additional coverage can be found in this story in the Albuquerque Journal."

Comments

Re:will this work?

[Henry V .009]

We do not test nuclear weapons underground, or above ground for that matter. America is confident in its computer simulations. But our confidence in our simulations is not the only factor. Nuclear weapons are never meant to be used. They are meant to deter (threaten). Therefore what is paramount is our enemies' confidence in our simulations.

Certification of the stockpile

[T5]

By law, the directors of the nuclear weapons labs (Sandia, Los Alamos, and Lawrence Livermore, IIRC) are required to certify annually the readiness of the nuclear stockpile. This has been a problem due to the lack of production of tritium in the US, with the exception of a small amount from Savannah River in South Carolina and just recently at the Tennessee Valley Authority's Watts Bar Nuclear Plant in Tennessee. Without sufficient quantities of tritium, the aging thermonuclear arsenal's decay of tritium puts the existing weapons at risk of not functioning within their design parameters. The only thing more frightening than a nuke that works is one that you can't rely on to work when needed. Thus, the directors have threatened to not certify the arsenal.

With this new computing power, the directors can now verify the status of even degraded weapons whose functionality was up till now a mystery and make better decisions about how to use the still small amounts of tritium being produced.

Re:What exacly are they trying to learn?

[thesupraman]

It's quite simple, they are trying to find out how long the current weapons will keep working, and how the rate of failure changes over time.

These devices contain quite an amount of rather radioactive material, which emits a lot of high energy particles, this causes other materials around them to change over time, therefore then need to know if they will stay safe, and will work if required.

The worked out how to build a 'big enough bomb' quite some time ago, but building new devices is expensive, as it blowing them up from time to time for testing, simulating the 'aging' devices is a much cheaper and simpler option, as well as providing supercomputing power for 'other' work.

FPS If this computer were used to run Quake 3

[Anonymous Coward]

First lets figure out how many times faster this computer is.

One of them they gave statistics that it did the work of 750 years worth of computer time in 39 days.
First lets figure out how many days there are in 750 years
750*365.25(accounting for leap year) ~= 273937

Thats 273,937 days in 750 years (give or take a couple of weeks)

Now 273,937 / 39 gives us are actual ratio which is a factor of 7024.
This means that the los Alsomething is 7024 times as fast.

Now a typical computer now a days can run quake 3 at around an average fps of 60.
7024 * 60 gives us the fps of the super computer.

Which is a grand total of 421,422 FPS!!!!

My only question... When can I buy one?

Re:Innovation...

[jimhill]

"We're lucky 'The National Nuclear Security Administration' even lasted through that mess of 8 years. Thoughts anyone?"

Yeah, here's a thought:

With all due respect, kwishot, like many Slashdot posters you're posting out of your ass and while you might win points among the equally ignorant you turn yourself into a laughingstock for those with a greater understanding.

The nuclear weapons complex is under the purview of the US Department of Energy. Almost since it was created from AEC/ERDA in the mid 1970s, DOE has been under attack for its poor organization, poor administration, and poor security record. Multiple panels and commissions and auditors spent their time submitting final reports and recommendations suggesting that the security aspect of the weapons complex be removed from DOE control or at least placed in the hands of a semi-autonomous agency.

After the _annus horribilis_ that was 2000 for Los Alamos, support both public and Congressional was high for these recommendations to be implemented. New Mexico Republican Senator Pete Domenici introduced legislation which would create the National Nuclear Security Administration as a semi-autonomous agency within DOE and that legislation passed with support from both parties and was signed into law by Democratic President Clinton. (Side note: then Energy Secretary Bill Richardson, former Democratic Congressman from, yep, New Mexico, took a well-publicized pummeling from members of both parties, not least of which was West Virginia's Democratic Senator Robert Byrd, who told Richardson that he could never vote to confirm Richardson for another government position again.)

I'm not a supporter of Clinton's -- his decision to appoint Hazel O'Leary as his first Energy Secretary will be a long, Long, LONG time in overcoming (among her since-revoked brilliant ideas was eliminating the color-coded badges which were used to provide a visual cue of a person's clearance level in favor of a less "discriminatory" monochrome badge). To fall to your knees and give thanks that an agency created in the closing year of his administration survived the eight year Reign of Terror just reveals that you don't have the first clue what you're addressing. Next time you're tempted to fire off a post on a topic to whose table you bring complete ignorance, may I suggest that you instead spend a few moments educating yourself -- and only then, if you feel you have something of value to contribute, should you click on "Submit".

Sorry - you're wrong.

[Werelock]

I actually did a paper a year ago on the need for a science court in US governmental decision making. One of the key points I kept running into in my research was that nothing science related a first year president pushes for, or even gets through, will be seen before he leaves office - even if he does two turns. Each project gets re-evaluated by the president, committees, congress, etc repeatedly throughout it's life. Usually the next president either downsizes it, kills it, upsizes it, or ignores it. They rarely say "that's cool as it is, just give them the same amount this year." Most science required 3 or 4 terms before results were truly seen.

So, in all actuallity, Clinton either started this or continued it on from his predecessor. GWB had jack to do with it other than to see the results and maybe a final bill.

-JD

Re:will this work?

[Waffle Iron]

Instead, what is usually done is to encase the hydrogen (tritium actually) in additional uranium or plutonium.

IIRC, tritium is very rare and only a few grams are used to "boost" the fission trigger. The main fusion fuel in most H bombs is a mixture of lithium and deuterium, which conveniently combine to form a solid chemical compound.

At any rate, in many bombs, the fusion is not even the main source of energy. It is used as a massive source of neutrons, instantly converting hundreds or thousands of pounds of dirt cheap unenriched uranium into fissionable fuel (unenriched uranium also avoids worries about dangerous multiple critical masses in one bomb). Many bombs get only about 1/3 of their energy from actual fusion, the rest is from the fast-neutron induced fission of the uranium blanket surrounding the fusion core. The end result orders of magnitude more fallout isotopes than a simple A-bomb.