Polywell Fusion

noosfractal · 2007-05-12 23:26:41

Robert Bussard (of Bussard Ramjet fame) says Polywell Fusion (a type of Inertial Electrostatic Confinement Fusion) is what we've all been waiting for. Unfortunately his US Navy funding ran out (after 11 years, during which he was under publishing embargo), so he has been making the rounds to raise funds.

Collection of links here ...
http://www.strout.net/info/science/polywell/

Previously mentioned in a propulsion context here ...
http://www.newmars.com/forums/viewtopic.php?t=2428

noosfractal · 2007-05-24 01:43:17

More info by Tom Ligon, an advocate who worked with Bussard on the project
to be presented at ISDC ...
http://isdc2.xisp.net/~kmiller/isdc_arc … ile_id=422
(it is a PowerPoint slide show)

C M Edwards · 2007-05-24 11:42:05

Well, Dr. Bussard never disappoints.

I hope this proves effective. Even if it never exceeds breakeven, I hope the Navy hangs on to the plans. It has great promise as a propulsion system.

I wonder if there's anything we can do to help him stump for it?

noosfractal · 2007-05-24 15:31:58

It would help if there were a technical write up a little more substantial than this IAC paper ...

http://www.askmar.com/ConferenceNotes/2 … 0Paper.pdf

The harshest criticism I've seen is that this guy ...

# Todd H. Rider, "A general critique of inertial-electrostatic confinement fusion systems", M.S. thesis at MIT, 1994.
# Todd H. Rider, "Fundamental limitations on plasma fusion systems not in thermodynamic equilibrium", Ph. D. thesis at MIT, 1995.
# Todd H. Rider, "Fundamental limitations on plasma fusion systems not in thermodynamic equilibrium" Physics of Plasmas, April 1997, Volume 4, Issue 4, pp. 1039-1046.

... says no system of the type Bussard is talking about can work. Tom Ligon says that Bussard has addressed the issues raised by Rider, but it'd be helpful if it were described in enough detail that an expert could say "that sounds plausible." I'm not sure that's happened yet.

cIclops · 2007-06-12 02:03:22

Bussard gave a lecture at Google, published his first paper and spoke on a recent Space Show. Although interesting, his ideas seem to have no independent scientific validation. After years of funding from the US Navy this may explain why they stopped funding his work.

publiusr · 2007-06-23 12:17:34

If we were to find a small black hole in space, surround it with a sphere, and at small sprays of water, the micro accretion disk might be compact enough to fuse...

noosfractal · 2007-12-15 21:02:26

Just an update on Polywell Fusion ...

http://www.defensenews.com/story.php?F= … &C=america

Dr. Bussard has died (Oct. 6), but the US Navy decided to refund his project in August (for $2m) and two of his closest assistants are continuing the project.

cIclops · 2007-12-16 07:55:19

There's no source reference for this new $2m US Navy contract .. only stories in various blogs that all copy each other, seems to be nothing on the EMC2 site either except a request for donations.

noosfractal · 2007-12-16 10:11:41

There's no source reference for this new $2m US Navy contract .. only stories in various blogs that all copy each other

The defensenews.com article mentions it. Are they not a trustworthy source?

Tom Kalbfus · 2007-12-16 10:55:33

I wonder why the Department of Navy is working on this, is there a case that says this type of nuclear reactor can only power a ship at sea? One would think this would be more the province of the Department of Energy. In the Navy this project has to compete with the Iraq War which Congress is short changing in hopes of making us lose, this will result in the redirecting of funds from other programs to the Iraq War. Thank You Nancy Pelosi.

noosfractal · 2007-12-16 15:02:51

I wonder why the Department of Navy is working on this, is there a case that says this type of nuclear reactor can only power a ship at sea? One would think this would be more the province of the Department of Energy.

Bussard claimed that the DOE was too committed to ITER to consider alternatives. Certainly, the orthodox view seems to be that IEC Fusion is not worth pursuing. The US Navy has a little more freedom to fund research that might yield strategic benefit, even if the chance of success is low.

Number04 · 2007-12-17 11:12:02

Either way, is sounds very exciting.. A new power source such as this would revolutionize the world. Once all the safety concerns were addressed it would be modified to every facet of our lives. And I’m sure a slice of the profits would all go to the US Navy.

JoshNH4H · 2007-12-17 14:58:17

This seems to be a major breakthrough in fusion. Imagine fusion NTR. Correct me if I'm wrong, but the only/biggest problem in fusion right now (and for the last 50 years or so) has been containment, right?

Terraformer · 2007-12-22 06:40:49

Containing the reaction, yes. Powerful magnetic fields have to be used to keep the superheated plasma in place, adding to the energy bill.

noosfractal · 2008-01-15 00:18:48

The 1st class team picking up from where Bussard left off is making progress ...

"We're not out trying to make a big splash on any of this stuff at this point," Nebel said. But he said he's hoping to find out by this spring whether or not Bussard's concept is worth pursuing with a larger demonstration project.
The initial analysis showed that Bussard's data on energy yields were consistent with expectations, Nebel said.
"We don't know for sure whether all that's right," he said, "but it'd be horrible for Mother Nature to give you what you expect to see, and have it all be bogus."

http://powerandcontrol.blogspot.com/200 … lasma.html

noosfractal · 2008-01-15 00:30:04

This seems to be a major breakthrough in fusion.

If it works, it will change the world.

Imagine fusion NTR.

Yeah

Correct me if I'm wrong, but the only/biggest problem in fusion right now (and for the last 50 years or so) has been containment, right?

More precisely, the goal is to achieve a Q factor (energy gain) greater than 20 ...

http://en.wikipedia.org/wiki/Fusion_energy_gain_factor

We can currently contain a piece of the sun, just not efficiently enough

JoshNH4H · 2008-01-15 15:21:18

That makes it quite a bit easier than I thought.

I could be wrong, but if you could contain a dense cloud of electrons/protons or ions in a plastic/ rubber container, that would cost nothing to maintain, but would have a very strong mag. field. I don't get why I havent seen this before. Is it impractical? (or to be more acurate, is it less practical that fossil fuels?)

noosfractal · 2008-01-15 17:49:54

That makes it quite a bit easier than I thought.

Well the ITER project is going to spend $US 15 billion to try and make it happen, so it's probably not as easy as you think.

I could be wrong, but if you could contain a dense cloud of electrons/protons or ions in a plastic/ rubber container, that would cost nothing to maintain, but would have a very strong mag. field. I don't get why I havent seen this before. Is it impractical?

To create a magnetic field, you need a _changing_ electric field, for example, produced by a moving charge. This is the idea behind the electromagnet ...

http://en.wikipedia.org/wiki/Electromagnet

... the ability merely to store charge is provided by batteries or capacitors (which is more like your idea) ...

http://en.wikipedia.org/wiki/Capacitor

JoshNH4H · 2008-01-16 15:29:14

but would the nuclei be repelled if this was done?

cIclops · 2008-01-17 02:36:28

The 1st class team picking up from where Bussard left off is making progress ...

Good news. This appears to be an independent look at Bussard's work. The team leader, Richard Nebel also seems to be a plasma physicist. Alan Boyle, a reliable science journalist recently wrote the original story 9 Jan 2008.

Among the comments added to Alan Boyle's blog is this one:

A quick comment on Mr. Katz's statement: I presume that he is referring to the work of Nevins and Rider from the early '90s. That work did not agree with the earlier papers of Bussard, Rosenberg and Krall which concluded that when you looked at the orbit averaged collisionality the system worked fine. Furthermore, the most complete treatise on this was published by Chacon, Barnes, Miley and Knoll in Physics of Plasmas in 2000. This work used the full bounce-averaged Fokker-Planck operator and concluded that IEC systems would indeed work.
So what should one conclude from this? When similar assumptions give you different answers, it means that the physics is sensitive to these effects (i.e. the devil is in the details). The only way to settle that issue is in the laboratory, which is what we intend to do. If we find that the collisionality is a problem, there are ways to innovate around it (see, for instance, Barnes and Nebel in Physics of Plasmas 1998).
R. A. Nebel, Los Alamos, NM (Sent Friday, January 11, 2008 4:25 PM)

Check back later for the results in the Spring.

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#1 2007-05-12 23:26:41

Re: Polywell Fusion

#2 2007-05-24 01:43:17

Re: Polywell Fusion

#3 2007-05-24 11:42:05

Re: Polywell Fusion

#4 2007-05-24 15:31:58

Re: Polywell Fusion

#5 2007-06-12 02:03:22

Re: Polywell Fusion

#6 2007-06-23 12:17:34

Re: Polywell Fusion

#7 2007-12-15 21:02:26

Re: Polywell Fusion

#8 2007-12-16 07:55:19

Re: Polywell Fusion

#9 2007-12-16 10:11:41

Re: Polywell Fusion

#10 2007-12-16 10:55:33

Re: Polywell Fusion

#11 2007-12-16 15:02:51

Re: Polywell Fusion

#12 2007-12-17 11:12:02

Re: Polywell Fusion

#13 2007-12-17 14:58:17

Re: Polywell Fusion

#14 2007-12-22 06:40:49

Re: Polywell Fusion

#15 2008-01-15 00:18:48

Re: Polywell Fusion

#16 2008-01-15 00:30:04

Re: Polywell Fusion

#17 2008-01-15 15:21:18

Re: Polywell Fusion

#18 2008-01-15 17:49:54

Re: Polywell Fusion

#19 2008-01-16 15:29:14

Re: Polywell Fusion

#20 2008-01-17 02:36:28

Re: Polywell Fusion

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