Tuesday, December 30, 2008

Mechanical Design: Open FEM

Open FEM is a mechanical design program that can help figure out the stresses and strains caused by the magnets in a Bussard Fusion Reactor. It is based on Scilab, a numerical computation program.

H/T Prometheus Fusion Perfection

Saturday, December 27, 2008

Free Plasma Physics Book

You can read reviews and buy a hard copy of Plasma Physics and Fusion Energyby clicking on the link.

Or you can get a pdf of the book at this detailed review or by going directly to the download link.

The book is very much tokamak oriented so the calculations have limited value for plasmas that are far from thermal equilibrium. However, the ideas presented are of interest to anyone working with plasmas.

Tuesday, December 23, 2008

Steampunk Fusion

Steam Punk Fusion

The picture you see above is a steam driven fusion reactor. I know what you are thinking. This is some kind of joke. It is no joke. General Fusion has a design that I think has an outside chance of working.

I was discussing it with some of the boys at Talk Polywell and I'd say it has no fundamental flaws.

Popular Science also gives some of the details of the machine and its inventors. The drawing at the top of the page shows a schematic of the machine that has 200 pistons. Now to give you some idea of the scale here is a picture of one of the pistons.
Steam Punk Fusion Piston

Huge sucker huh? Now imagine 200 of them all firing away at the rate of once a second. When the piston hits (and yes it will hit) the end of the cylinder it will be going about 250 mph and it will induce a shock wave into a sort of ball of liquid lithium and lead. But first two rings of counter rotating plasma will be shot into the middle of the rotating metal and then all the steam (yeah steam) driven pistons will fire and hit the molten metal with a timing of better than one microsecond.

Can it be done? My rough calculations at the above Talk Polywell link say yes. Not easy, but possible. So would I put money on it? Not me. But I'm an IEC Plasma Fusion type of guy. However, if the idea excites you (a steam driven fusion reactor) I'd say it has as much a chance of working as anything being done now. Definitely worth a shot. And besides how many of your friends can say they are investing in a steam driven fusion reactor? It has got to be worth some bucks just for the conversation starter value alone.

Rick Nebel Updates The Latest News

From Cosmic Log:
First of all, our work has been peer reviewed. An independent panel of experts has looked at these results. I don’t believe that there was anyone on the panel who has less than 40 years experience working with magnetic confinement. It included senior professors and people who have managed the fusion program. We asked them for their honest opinions and that’s exactly what we got. We are proceeding with our program in line with their recommendations.

Secondly, the talk-polywell blog has a large variety of people who post there. There are Phd plasma physicists as well people from the general public. I think that’s a good thing. Science needs to be accessible to people.

Rick Nebel (Sent Saturday, December 20, 2008 12:08 PM)
Yes, there are neutrons and the numbers are consistent with the plasmas we are measuring. However, neutrons can be deceptive. A lot of fusion researchers have gotten in trouble in the past by relying on these types of measurements. You need to know where they come from and that's difficult to measure.

R Nebel (Sent Saturday, December 20, 2008 4:31 PM)
Discussed at Talk Polywell. This is one of the places (among several) at the board where the news is being discussed.

Liquid Cooled Grid IEC Reactor

Roger at Talk Polywell provides a link to experiments done with a liquid cooled grid Farnsworth - Hirsh type IEC Fusion device. The device uses a magnetron type ion injector.

You can read about it at RTF Technologies.

I especially recommend the paper describing the construction [pdf].

Wednesday, December 17, 2008

IEC 2008 - Kyoto

I just received a report on the IEC Fusion 2008 conference from Joel Rogers - one of the participants. This is a report of the conference schedule which has links to the abstracts of the papers presented. You can also see the poster for the conference [pdf] which has a very nice picture of a temple on the Uji-Campus of Kyoto University.
Uji is surrounded by beautiful landscapes centering on the Uji River with more than a thousand years of history. It is abundant with historical assets including Byodoin Temple and Ujigami Shrine, both of which are registerd in the UNESCO world heritage list. A lot of historical assets and autumn tints in early December attract many visitors to Uji.

The Byodoin Temple was first a villa owned by Fujiwara Michinaga, the model for the hero Genji in the Tale of Genji. Then in 1052 it was converted into a temple by his son. The central hall in the above photo is popularly known as Hoohdo (Phoenix Hall), an image of which is found on 10-yen coins.
Here is the abstract of the talk [pdf] Dr. Rogers gave.
IEC Polywell[2] is a candidate for commercial power generation. Particle-in-cell simulation was used to follow the time sequence of plasma development starting from neutral deuterium gas in a cubic Polywell. The left figure below shows electrons flowing in and out of the core along 8 cusp lines. The 8 rectangles are 1.0kG coil-magnets separated by 30cm (inside core diameter) and biased to 15kV. Electron guns (5A) are centered on the 4 vacuum tank walls, held at 0V. The center figure shows the ion distribution at Beta ≅ 1 density. Bounded by a 2cm thick shell, the interior ion population is uniform inside the shell. The shell is composed of ions that have slowed prior to reflecting at the edge of the potential well. The right figure shows the ion velocity (U) population. The flat top indicates uniform inside magnitude, |U| = 1.3x10E6m/s (18keV). The fusion rate was computed as n2·<σ(v)·v>·a3/2, where n is the ion density (n=1.1x10E11/cm3), σ is the parameterized DD fusion cross section, v is the ions’ relative velocity, and a is the diameter(20cm) of the ~cubic volume inside which the velocity is uniform. Substituting the simulated n, v, and a, resulted in a fusion rate prediction of 9x107 fusions/s, in fair agreement with Bussard's measured WB-6 neutron rate[2]. The simulation predicts the following features of Polywell: (1) Electrons circulate out and in freely along cusp lines. Very few electrons hit the magnets. (2) Ions are trapped in an electrostatic potential well, which maintains a steady state, spatially uniform, monoenergetic ion population long enough for substantial fusion to occur.
(3) The surface density of trapped electrons corresponds to a Beta value on the order of unity.

Particles reaching the tank wall will generate electricity efficiently while particles hitting the magnets will generate electricity less efficiently. The effective power gain factor (Q) can be estimated as the ratio of fusion power output to the portion of electric power input spent to replace ions hitting the magnet boxes. Simulated Q-factor as a function of device size has predicted the size of a steady state, break-even (Q=1) device which needs to be tested.
The pictures mentioned are included in the pdf.

WB-6 Results Confirmed - Continuous Operation The Next Step

Alan Boyle at Cosmic Log announces the results of the WB-7 Bussard Fusion Reactor (BFR) experiments. And the results? No show stoppers so far.
An EMC2 team headed by Los Alamos researcher Richard Nebel (who's on leave from his federal lab job) picked up the baton from Bussard and tried to duplicate the results. The team has turned in its final report, and it's been double-checked by a peer-review panel, Nebel told me today. Although he couldn't go into the details, he said the verdict was positive.

"There's nothing in there that suggests this will not work," Nebel said. "That's a very different statement from saying that it will work."

By and large, the EMC2 results fit Bussard's theoretical predictions, Nebel said. That could mean Polywell fusion would actually lead to a power-generating reaction. But based on the 10-month, shoestring-budget experiment, the team can't rule out the possibility that a different phenomenon is causing the observed effects.

"If you want to say something absolutely, you have to say there's no other explanation," Nebel said. The review board agreed with that conservative assessment, he said.

The good news, from Nebel's standpoint, is that the WB-7 experiment hasn't ruled out the possibility that Polywell fusion could actually serve as a low-cost, long-term energy solution. "If this thing was absolutely dead in the water, we would have found out," he said.

If Polywell pans out, nuclear fusion could be done more cheaply and more safely than it could ever be done in a tokamak or a laser blaster. The process might be able to produce power without throwing off loads of radioactive byproducts. It might even use helium-3 mined from the moon. "We don't want to oversell this," Nebel said, "but this is pretty interesting stuff, and if it works, it's huge."
The next step in my opinion should be a continuously operating version about the size of WB-7. A device I used to call WB-7x and will probably be called WB-8.

Here are some links to what I think a liquid nitrogen (LN2) cooled magnet coil WB-8 (WB-7x) should look like.

Design Issues including laboratory equipment.
Reactor Vessel Requirements.
LN2 Storage
Magnet Power Supplies
Reactor Building And Reactor Controls
Power Supplies Update #1
Reactor Building Sketches
Electron Guns
Lab Tools
Other Instrumentation - Mass Spectrometer
Research Speed
PID Loops And Leak Valves
Orifice Sizing for leak valves.
Thinking About Control
Ionization Pressure Gauges
Turbo Pump Ratings
Gas Valve Design
Data Collection
Vacuum Pumping
Transimpedance Amplifiers
The First Wall Problem
WB-6 Shopping List
Standardizing Fusion Test Reactors
Gauging With Intent
CAN Bus And System Control
Magnetic Field Measurement

For those of you not up to speed on the basics may I suggest:
Easy Low Cost No Radiation Fusion
The World's Simplest Fusion Reactor Revisited

And for those of you who would like to join in on the research at a very modest cost may I suggest Starting A Fusion Program In Your Home Town. There is a lot that can be learned from these very simple devices and some simple instrumentation. There is so much we don't know yet.

H/T Instapundit

Tuesday, December 16, 2008

Amateur Nuclear Fusion - The Book

Amateur Nuclear Fusion
I just came across a book Amateur Nuclear Fusion that is the tale of one guy's efforts to make neutrons in his basement. Here is the blurb from the book:
Here's a look inside an amateur lab that does nuclear fusion. I outline the basic principle of the Farnsworth fusor, and describe my fusor in detail, accompanied with tales of its construction.
The book is not expensive at $12.50 but even better you can get it as a free down load. Both are available at the above link.

H/T Open Source Fusor Consortium

Friday, December 12, 2008

Incoming Energy Secretary On Bussard Fusion

In this Google Tech Talk from about 28 February 2007 you can see Incoming Energy Secretary Steven Chu discussing what he knows about Bussard Fusion about 1 hour 1 minute and 10 seconds into the video. The rest of the talk is about alternative energy, power sources for the future, and how to run a good development program. And what does he know about Bussard Fusion Reactors? Not much. He is looking into it.

I got the heads up from cybrbeast at Talk Polywell.