Fusor Vacuum Pumps

I'm going to start with turbo pumps and then add roughing pumps later. I'm going to add some compression ratio numbers which will determine final pressure. Plus prices for pumps and controllers if I can find them.

Adixen ATH31+. 1E11 N2, 1E5 H2 Compression Ratio
Aprox Prices:about $4,700 pump, about $1,700 controller, about $600 required accessories. 4 1/2" CF High Vacuum connection.

Varian Turbo V81M. 5E8 N2, 7E3 H2 Compression Ratio
Aprox Prices $5,900 Pump + Controller. CF 63 High Vacuum connection

Pfeiffer TMU 071YP >1E11 N2, 1E5 H2 Compression Ratio
Aprox Pricesabout $4,700 pump, about $1,200 controller,

Oerlikon Leybold TURBOVAC 50 2E6 N2 Compression Ratio
Aprox Prices:about $3,300 pump, about $1,500 controller. CF 63 High Vacuum connection

Fusor Power Supplies

I think a supply in the 15KV to 30KV range with an available current of 30 mA would be good for general purpose experimentation and neutron generation. It should be adjustable, regulated, and current limited. It should be immune to the usual lab accidents such as shorts and current bursts. It should have an emergency fast trip.

I have some candidate mfgrs:

Glassman High Voltage Inc.
Spellman High Voltage
Universal Voltronics

Fusor Vacuum Vessel

The Kimball Physics spherical cube and expanded spherical cube seem like very good designs for the project and the price is right.

I like the 4.8", 6.5" and 8.4" sizes. The prices run from $1,700 to $9,600 depending on size and features desired.

Here is what I think are useful sizes and prices:

MCF450-SC60000 4.8" ID; 57.91 cu inches, .95 liter Volume; 6 - 4 1/2" CF (DN63) Vacuum Ports; $1,700

MCF450-ESC60800 6.5" ID; 143.79 cu inches 2.36 liter Volume; 6 - 4 1/2" CF (DN63), 8 - 2 3/4 CF (DN40) Vacuum Ports; $3,550

MCF600-ESC600000 8.4" ID; 310.34 cu inches 5.09 liter Volume; 6 - 6" CF (DN63) Vacuum Ports; $6,800

Boron Vapor Pressure

This question of Boron vapor pressure has come up a number of times in various discussions so I think a reference post is a good idea.

From Boron Properties:

Vapor Pressure: 4.6 x 10-4 to 8.5 x 10-3 mm @2200K

From Boron - Yahoo Answers:

Temperature/Vapor pressure:

2348K 1 Pa
2562K 10 Pa
2822K 100 Pa
3141K 1 k Pa
3545K 10 k Pa
4072K 100 k Pa

Constructing a Fusor - Joseph Zambelli

Joseph Zambelli has built a fusor. He starts out with a very nice picture of his device.

This Inertial Electrostatic Confinement Fusion (IECF) fast neutron generator is a complete, easy-to-operate tabletop system. As presently configured, it produces up to 6.75E5 2.5 MeV neutrons per second with an acceleration voltage of 42 KV and a current of 18mA, at a pressure of 11.5 mTorr, with a start-up time of 10 minutes or less. It can easily be upgraded to yield even higher neutron production rates if so desired. This design has extremely low operational costs, and requires only a single 120V outlet for power. It features an 8” UHV Stainless Steel spherical, multi-port chamber evacuated with turbo-drag and rotary backing pumps.

He has another picture and link page here. The link page has links to the following the following sections:

Theory
Construction
Operation
Demonstration System
Further Links

Constructing a Fusor - Longwood University

I just came across this interesting report on the construction of a Farnsworth Fusor by Andrew Grzankowski at Longwood University, Farmville, Virginia.

Over the Summer of 2007, physics major Andrew Grzankowski worked with Longwood faculty member Keith Rider (Chemistry) to construct a Farnsworth Fusion Reactor. Here’s a breakdown of the project.

In the end notes there are a series of links which I am going to reproduce here.

Fusor.net

Original patents (H-M Fusor)[pdf]

Thesis – Carl Dietrich 2007 (MIT)[pdf]

Tom Ligon – The world’s simplest fusion reactor, and how to make it work[pdf]

Todd Rider – Is there a better route to fusion? (MIT)[pdf]

Prof. Kim Molvig – Fusion without neutrons using p-B11 (MIT Fusion Seminar)[pdf]

EMC2 Fusion Development Corp. – Inertial Electrodynamic Fusion: The answer to interplanetary space travel? - Tom Ligon's Presentation, 26th International Space Development Conference, May 2007 [ppt]

Small Vacuum Vessel Suppliers

Here is a handy list of vacuum vessel suppliers suitable for Fusor Construction. I will be adding to the list from time to time.

Meyer Tool and Manufacturing Oak Lawn, Illinois

Kimball Physics Wilton, New Hampshire

Kurt J. Lesker Company Clairton, PA

MDC Vacuum Products, LLC Hayward, California

Nor-Cal Products Yreka, CA

Trinos Vacuum Systems, Inc. Chicago, Illinois

A&N Corporation Williston, FL

Atlas Technologies Port Townsend WA

Sci Quip - Used Eqpt.

Oerlikon Leybold Flanges and Fittings

Link Added To Sidebar

I have added IEC Fusion Web Ring to the sidebar. It links to amateur fusion efforts.

Fusion Report 15 May 008

In Picture Of WB-7 Bussard Fusion Test Reactor Available I reported that there was a picture of the WB-7 Fusion Test Reactor available. (Well duh). I must sadly report that it is no longer available. Instead EMC2 Fusion has replaced it with a picture of a plasma test of the fusion reactor using Helium gas. Yeah! We are another small step on the way to fusion power. Or to proving you can't get there from here. Depending.

Reactor Size

I was rereading Sekora's paper on POPS [pdf] and came across this gem.

It is very difficult to achieve field strength approximately 50-100 kV/cm without causing arcing.The maximum field strength is governed by the Paschen curve.

So let us look at what a decelerator BFR might look like. Reaction volume 1 meter radius. That is a given. Let us assume 200 KV drive voltage. If we assume a voltage of 20KV/cm that gives 10 cm to zero voltage. Then assume 2 MV decelerator voltage. That is 1 meter. So the total radius is 2.1 meter. At 40" per meter (roughly) That is 84" radius or 168" diameter. About 14 ft in diameter for a 100 MWth reactor. Suppose we go to 40KV/cm (about the limit). That would be 1 meter reaction space. About 5 cm to zero voltage. And 50 cm for the decelerator. That would be 1.55 m radius. 3.1 m diameter. About 124" or a little over 10 ft in diameter. So odds are the reactor will be between 10 ft and 15 ft in diameter for a design with direct energy conversion. That would fit on all but the smallest ships.

Standardizing Fusion Test Reactors

In my recent post Starting A Fusion Program In Your Home Town I talked about expanding the fusion design and testing environment to increase the rate of progress in the development of a power producing reactor.

The lead Bussard Fusion Reactor (BFR) experimenter, rnebel, has read that article and has chimed in here with his thoughts.

One of the things we have been considering is selling a "turnkey" version of the WB-7. In this case we would design, build, license and deliver an operating Polywell, probably on the scale of the present machine. Operator training and tech support would also be part of the deal. The model is to use a plug and play concept where the user could substitute their own parts (electron sources, for instance) in an open architecture system. This is similar to what IBM did with the PC in the early 80s. It would give people who are interested in Polywells a chance to develop their own new patentable concepts and new companies without having to go through the entire learning curve that we have been on for the past several years. This struck us as a way to jumpstart the industry and get a lot of new ideas and people involved in Polywells. These devices could be funded through government grants (we have found a mechanism) or privately. I think we could do a turnkey machine for a ~ $500k-$1000k depending on how many people are interested. The idea would be for the government to make grants to institutions and then we would be able to competitively bid on providing the hardware. Ideally, I would like to see at least one Polywell in every Congressional district in the US. Since the cost is cheap, this is a tractable. Is this something you might be interested in?

My reply went as follows:

Sign me up.

I think it might also be useful to do a $10K to $100K fusor type device for those on a more limited budget. Jr. Colleges etc. There is a lot that can be learned from such a device that would help with more efficient (Pollywell) devices.

BTW in other places (fusor forum) I have made the evolution of the computer hobby argument.

Great minds etc.

Also a range of devices and power supplies. i.e. 25KV, 50KV and 100KV pulsed supplies. Then the same range of continuous operation supplies. Same for the reactors. Pulsed and continuous operation. The equipment should be standardized as much as possible - at least for the starter kits so we could get the efficiencies of mass production. Also standardized test equipment. Standardized control.

If we had 435 tests going on at once in each district that would cause the Congress critters to all get behind the fusion push. Very astute. That was sort of my idea.

Again - contact me and tell me how I can help. I'm rarin' to go.

Simon

Any venture capital people who would like to start something - contact me.

Reaction Rate and Drive Voltage Spread Sheet

You can down load it at Reaction Rate and Drive Voltage.

Starting A Fusion Program In Your Home Town

It is getting to the point that to make advances in the field of IEC Fusion collaborative efforts will be required due to the range of knowledge required and the cost. The individual with the home built fusor is not a thing of the past by any means, but it is not the wave of the future. I have been contacted by people from Jr. Colleges who are interested in doing fusion research so that is probably the place to go. Get your local Jr. College or College interested.

Here is one College doing work in the field that I have provided some advice and direction to: Peninsula College Fusion experiments. Here is another link with more details to the Peninsula College Fusor Project. There is also this link describing the genesis of the project, the cost in materials ($3,000), and the educational benefits. They also have a very nice Resources Link page.

In that vein I have contacted Rock Valley College and Rockford College (in Rockford, Illinois) to see if I couldn't get something started. We shall see if anything comes of it.

Here are some links to get those interested started:

IEC Fusion Technology blog
Open Source Fusor Research Consortium II
The World's Simplest Fusion Reactor Revisited
Disciplines and areas touched upon in fusor construction

Standardized Fusion Test Reactors.

I'm going to add a list of Colleges and Universities that are working on small fusion (budgets under $100,000 - places like The University of Wisconsin at Madison which has a rather well funded IEC program - well above $100,000 - will not be on the list). If you get something going in your home town send me some info. I'll add you to the list.

UMass Lowell.
A Community College - no name given

Fusion Report 06 May 008

Richard Nebel tells about plans for commercializing the Bussard Fusion Reactor (BFR) at Talk Polywell. Richard starts off discussing who owns the BFR technology and patents. DOD is The Department of Defense. Currently the US Navy is funding the research.

...EMC2 owns the patents and the commercialization rights. DOD retains the right to use the technology free of charge. That's a pretty standard arrangement.

As for DOD taking control of the technology, I think that's pretty unlikely. The most similar parallel to this that I can think of was the development of fission power. Both nuclear fission propulsion and commercial power were developed in parallel. It isn't a coincidence that both systems are LWRs. I expect a similar situation here. Everyone that I have talked to at the DOD understands that energy supply is a major national security issue. It's not in the national interest of the US to keep this technology from going commercial. Furthermore, this project has never been classified. Fusion research world-wide was declassified in 1958 by international treaty.

Finally, I appreciate your concern about research being slowed down by the lack of dialogue. My previous research at LANL (POPS for instance) was always public domain. The reason we did it that way is because we figured that the patents would run out before we could commercialize it and the benefits of having it critiqued outweighed the drawbacks of getting "scooped". I still feel that way, but I have a little different responsibilities at EMC2. We have a responsibility to get this technology developed in a timely manner and I also have a responsibility to look after the interests of our employees and the corporation.

From the way he is talking he seems pretty confidant of success. I sure hope he is right. Dr. Nebel also reports that the EMC2 contract with the Navy runs through August. So that gives some idea of when we might know the answer.

To get an idea of what success would mean check out:

Easy Low Cost No Radiation Fusion also check out the IEC Fusion Technology blog.

The side bar at IEC Fusion Technology blog has links to various discussion groups. They can be found under the heading Working Groups.

A good tutorial and a history of the project before the US Navy resumed funding can be found at: World's Simplest Fusion Reactor Revisited.

Fusion Report 05 May 008

Richard Nebel reports at Talk Polywell that the EMC2 contract with the Navy runs through August.

Fusion Report 02 May 008

Here is a progress report from MSNBC's Cosmic Log about the status of the Bussard Fusion Experiment, WB-7.

Currently, the most promising path toward electrostatic fusion runs through Santa Fe, N.M., where a team at EMC2 Fusion Development Corp. is currently trying to validate Bussard's results. The team's leader, Richard Nebel, told me this week that it's still too early to gauge how promising the Bussard fusion device could be.

"We're getting high-power plasma," he said. "We don't have answers ... [but] we're far enough along that we know we're going to get answers."

If you want to learn more about Bussard's IEC Fusion here is a good place to go:

Easy Low Cost No Radiation Fusion

The side bar here has links to various discussion groups. They can be found under the heading Working Groups. You might be especially interested in the Talk Polywell discussion group where Richard Nebel can often be found commenting and answering questions.

The World's Simplest Fusion Reactor Revisited

Tom has graciously provided a pdf of his most recent Analog article The World’s Simplest Fusion Reactor Revisited for your edification and enjoyment. Please read the following and then click on the link provided for your own copy. Tom sends his regards to all. Enjoy!

Copyright 2007, 2008, by Tom Ligon. This article was first published in the January- February 2008 edition of Analog Science Fiction and Fact. Special edition with postscript for iecfusiontech.blogspot.com and fusor.net. This document may be downloaded, printed out, or linked from other sites, but please do not re-post it on other websites, or re-publish it, without the author’s permission. If corrections or updates are needed, I’d like a limited number of copies to track down.

The World’s Simplest Fusion Reactor Revisited