[Joeviocoe]

Has the new Tungsten crown regularized the filaments, and yielded any higher gains?

[Joeviocoe]

zapkitty wrote:

This is an unexpected collaboration.
http://www.guardian.co.uk/environment/2012/may/25/iranian-team-collaborate-us-nuclear

Good news!

And the Guardian article is okay if brief…

… but I wish that pic of a tokamak-style toroid could have been of something more relevant instead 🙂

Yeah, people associate the Tokamak picture with Billions of dollars of financial waste and a project that will take 30 years to complete.

[Joeviocoe]

delt0r wrote: I now work in Evolutionary biology (was physics). I assure you its not as good as you think. In fact if you understand whats going on, there are often simple things you can change for improvements that a mutation selection thing never gets. For example solar cells are far more efficient that photosynthesis.

First seek to understand….

Sorry for the flashback bump…

I don’t think that is a fair comparison.

1) Photovoltaics generates electricity, Photosynthesis generates complex carbohydrate molecular chains. Not exactly a fair comparison. Electricity production by means of using a single photo to knock off a single electron is by far more simple at task than the complex dance of chemistry to convert H20 and CO2 to much longer chains of molecules. It is not as efficient because there are a LOT more side and half reactions that all contribute to loss.

2) Natural Selection cares only about replication, not pure efficiency. If higher efficiency is rewarded by better means to replicate, than natural selection could and would go that route. But that is not always the case.

Example. Two plants:
Rather than increasing the efficiency (energy per square inch of each leaf surface area) which would yield only gains for itself, a plant may opt to simply grow taller, and thus compete directly with the other plant and yield gains for itself AND simultaneously doing harm to it’s competitor. Shading the other plant, so it dies and the nutrients and water are then available for the taking.

[Joeviocoe]

dennisp wrote: Joe I think ikanreed knows the difference. His point is that if they were able to maintain that power output for 1/8 second, it would be the the same energy as Hiroshima. They actually maintain it for a much shorter span of time, but the comparison still gives a good impression of the power level they’re talking about.

Sorry if that came across as a bit harsh. The reason I am so adamant about not comparing things like that, is because it can foster unscientific reasoning.

And more importantly, newcomers or any less educated folks in politics or the media… could think that this facility contains that much energy at any given time.. and a simple accident (like the beam not shutting off for 1/8th of a second) could vaporize the city of Livermore, California.

BTW, 2 Megajoules is about 0.55 kilowatt-hours. About half the energy in your standard 12 volt Car Battery. I wouldn’t want anyone comparing that to an Atomic Bomb.

[Joeviocoe]

dennisp wrote: Joe I think ikanreed knows the difference. His point is that if they were able to maintain that power output for 1/8 second, it would be the the same energy as Hiroshima. They actually maintain it for a much shorter span of time, but the comparison still gives a good impression of the power level they’re talking about.

I am not a fan of that comparison. It is misleading more than “a good impression”.

Here’s a better impression. Hiroshima bomb was 60 trillion joules, NIF shot was 2 million joules. That is a difference of 30 million times! There is no “maintaining” for anywhere near a second.

Comparing pulse power machines that operate at infinitesimal smaller pulses than a “second”… to a constant power device that would and could run for seconds minutes and/or days… is, well, nonsense.

There is no lower limit to time. It gets smaller and smaller. The reason why I think that comparison is misleading, is because it plays on some people’s inability to comprehend things too large or too small. We perceive the World of the medium. – Alan Watts.

The fallacy:
“So the NIF Laser fires in a couple of nano seconds, that is small. 1/8th of a second is small too. They must be comparable”. The difference between 4.5 nanoseconds and 1/8 of a second … is the same difference between 1 second, and about a year.

Even if you wanted to, and the Lasers could sustain several minutes of 500 trillion watts…, the entire NIF facility, could not hold that much energy in all of their storage systems. They would literally need about 15 Thousand Tons of TNT to store that energy chemically. Or an actual mass of nuclear material (in which case would be an exact comparison).

[Joeviocoe]

annodomini2 wrote: http://www.liquidmetal.com/

Don’t know if this is of any help, but something to consider.

Too much resistivity. By far. Not a good conductor.
190 microOhms per centimeter. Compared to Aluminum 380 which has 6.5 microohms per centimeter. Copper wasn’t even mentioned.

[Joeviocoe]

asymmetric_implosion wrote: but they were using aluminum cans as the metal shell.

Like soda cans?

[Joeviocoe]

Tulse wrote: I admire the gumption and out-of-box thinking of the General Fusion folks, but their approach seems absolutely absurd to me. I can’t imagine the timing and tolerances needed being sustainable over the frequency of compressions needed to produce practically useful power.

Not to mention the maintenance. The more moving parts you have, and the faster/harder they operate… leads to some significant challenges.

[Joeviocoe]

ikanreed wrote:

NIF released their April update halfway through May this month. Usually they’ve been very punctual. I thought the following quote of note:

A NIF Facility Maintenance and Reconfiguration period began on April 25 and was scheduled to continue until May 15. The NIF team’s goal is to upgrade NIF’s peak power to 500 trillion watts in preparation for this summer’s experiments.

That’s insane. The Hiroshima bomb was in the neighborhood of 60 trillion joules of energy. They’d pass that in an eighth of a second. I don’t pretend that’s even near how long they’re firing, but that’s still an unimaginable amount of power.

No, that was 500 Trillion WATTS not JOULES. The highest NIF has gotten I believe was 1.8 Megajoules per shot. Maybe a bit higher.

[Joeviocoe]

Ivy Matt wrote: Design Engineering has an article on General Fusion, viewable online (click on the cover image). The Canadian company is hoping to achieve proof of concept in 2015 and have a commercial reactor available by 2020. The article mentions ITER and NIF, but a quote from Dr. Paul Wilson of the University of Wisconsin-Madison also appears to contain an oblique mention of other contenders:

“I think a horse race metaphor works well,” Wilson observes. “We’re probably going to see one horse pull ahead and then maybe another catch up and lead the group for a while, and so on. This will be an interesting decade.”

Where have I heard that horse race metaphor before? 😉

(Hat tip to jcoady at Talk-Polywell.)

Nice article.

“General Fusion will be holding an important physics test this summer of their plasma compression device. If all goes well, it is likely to change the global fusion mindset”
I doubt it. The will have to prove feasibility that this device can scale to a size that produces more energy output than input. So even if the physics work out, that doesn’t mean a power plant is feasible or practical… and the global fusion mindset will stay with the Tokamaks and 50 years away.

But I do like the approach. A steampunk fusion approach 🙂

[Joeviocoe]

Tulse wrote:

The Navy could really benefit from Aneutronic fusion because of the lack of need for sheilding and even better fueling (no need for tritium breeding) and waste (no activation).

That’s true, but of all the armed forces they have the least issue with heavy shielding and radiation handling. Their craft can easily deal with both, far more so than the Air Force or Army. (After all, they are the only branch which currently operates nuclear-powered vehicles.)

I would think the Army would be even more eager for clean, easily-transportable generators (for bases), and the Air Force as well (light enough reactors could power an unmanned bomber for months, and a purely electric plane would have a negligible heat signature).

The Army has access to large amounts of petroleum based fuel. So their efforts to have a nuclear program ended early in 1977 and was thought to be a “Solution in search of a problem”. The Navy, especially the submarine fleet, endangers itself when it needs to be resupplied. The Army is does have some recent problems getting constant supplies of fuel… but it is far cheaper and easier to secure petroleum supply and transport than it is to deal with building a Nuclear plant in someone else’s country.

I don’t think even the lightest of fission reactors would work yet for bombers…
In such a tight package, the shielding must be thick and heavy to protect the electronics/avionics. Going unmanned doesn’t remove the need for shielding.
RTG’s mabye. Possibly even battery UAVs recharged from ground or space via microwave.

[Joeviocoe]

Tulse wrote:

I don’t think Poylwell is considering Aneutronic seriously just yet. They want a working powerplant using D-T first.

Frankly I think that is a very wise strategy for them — the first “alt-fusion” approach to reach breakeven will be a big winner, even if it is with more “conventional” radioactive reactions that are nonetheless far easier to produce in principle than pB11. And the Navy is used to dealing with fission reactors, so the radiation from a DT reactor would likely not be an issue.

I think the Navy is more interested in the promised 100 MW power output. Which is about the same as standard submarine fission reactors. But for a lot cheaper and much better fueling and waste economics.

The Navy could really benefit from Aneutronic fusion because of the lack of need for sheilding and even better fueling (no need for tritium breeding) and waste (no activation).

[Joeviocoe]

On the information dissemination front… The Focus Fusion society is Lightyears ahead of Talk-Polywell. Being funded by the Navy means that we only get periodic updates and those are VERY vague and missing the good details. And the lack of information seems to fuel more comments and debate. They have longer discussion threads it seems… and also they attract some of the fringes of science too.

I would certainly like to see an old-fashioned race between Focus Fusion and Polywell. But I don’t think Poylwell is considering Aneutronic seriously just yet. They want a working powerplant using D-T first. But also, they are both on different scales of power output. Focus Fusion will be capped at 5MW while Polywell might exceed 100MW.

[Joeviocoe]

https://www.neco.navy.mil/synopsis_file/N6893609C0125 _Redacted_JA.pdf

[Joeviocoe]

Would any voltages greater than 60 kV be even relevant to LPP’s DPF?

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