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The Polywell Guy

(25 posts)
Fri Jun 6, 2014, 08:16 PM Jun 2014

Nuclear Fusion - US Navy Publishes on Polywell.

Hello All,


The Polywell is an idea for a fusion reactor.

It is based off of the fusor: The Worlds' Simplest Fusion machine.

The Fusor was recently featured on The David Letterman Show.



A magnetic field traps electrons. These make an electric field. That field can heat ions to fusion conditions.
It is a possible path to fusion power. The US NAVY spent several millions building, testing and running this machine.

This is what they built:

[IMG][/IMG]

Download the paper here.

==========
Abstract:

We report experimental results validating the concept that plasma confinement is enhanced in
a magnetic cusp configuration when ? (plasma pressure/magnetic field pressure) is of order unity.
This enhancement is required for a fusion power reactor based on cusp confinement to be feasible.
The magnetic cusp configuration possesses a critical advantage: the plasma is stable to large scale
perturbations. However, early work indicated that plasma loss rates in a reactor based on a cusp
configuration were too large for net power production. Grad and others theorized that at high ?
a sharp boundary would form between the plasma and the magnetic field, leading to substantially
smaller loss rates. The current experiment validates this theoretical conjecture for the first time
and represents critical progress toward the Polywell fusion concept which combines a high ? cusp
configuration with an electrostatic fusion for a compact, economical, power-producing nuclear fusion
reactor.
8 replies = new reply since forum marked as read
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Nuclear Fusion - US Navy Publishes on Polywell. (Original Post) The Polywell Guy Jun 2014 OP
Not happy about those Bremsstrahlung numbers. joshcryer Jun 2014 #1
Page 7, only Hydrogen isotopes FogerRox Jun 2014 #4
I wonder how Lockheed is doing. SkatmanRoth Jun 2014 #2
I Would bet money Lockheed is also doing this. The Polywell Guy Jun 2014 #7
This paper is apparently about a smaller polywell built after WB-8 to work on start up FogerRox Jun 2014 #3
IS this the Money quote? FogerRox Jun 2014 #5
So, last I read, the theory predicted energy surplus at 1-2 more size doublings. phantom power Jun 2014 #6
AFAICT a slightly larger size FogerRox Jun 2014 #8

FogerRox

(13,211 posts)
4. Page 7, only Hydrogen isotopes
Sun Jun 8, 2014, 05:54 PM
Jun 2014

SO thats not D-D fuel or PB-11.

If I'm reading page 5 correctly the brem goes down at a higher power of electron injection (700Mw).

Remember the ration-mix of hydrogen (Proton) and Boron makes brem go or down. IIRC Both Dr Bussard & Tom Ligon suggested about 9-1 ratio.

The Polywell Guy

(25 posts)
7. I Would bet money Lockheed is also doing this.
Sun Jun 29, 2014, 02:47 PM
Jun 2014

I am 80% sure that Lockheed is doing exactly the same thing.

They are trapping high pressure, high density plasma in a cusp system.

I just finished a post talking about this (2 months of work):

http://thepolywellblog.blogspot.com/2014/06/fusion-in-upheaval.html

Here are some images from the post, to entice you to read it:

[IMG][/IMG]

[IMG][/IMG]

[IMG][/IMG]

I will probably re-post this elsewhere.

FogerRox

(13,211 posts)
3. This paper is apparently about a smaller polywell built after WB-8 to work on start up
Sun Jun 8, 2014, 05:42 PM
Jun 2014

We knew there was an issue with electron injection in WB-8.

This is the best news since Wb-6 was tested in late 2005.

FogerRox

(13,211 posts)
5. IS this the Money quote?
Sun Jun 8, 2014, 06:05 PM
Jun 2014
the expected D-T fusion power output would be 1.9 GW for a D-T cross section of 1.38 barns at a center of mass energy of 30 keV.


Excuse me, did that read 1.9GW with DT? That might mean the same size reactor using PB-11 would yield about 1.3 Gw. And yes, scaling has now been proved via real experiments.

phantom power

(25,966 posts)
6. So, last I read, the theory predicted energy surplus at 1-2 more size doublings.
Sun Jun 8, 2014, 06:38 PM
Jun 2014

What's the state of play on that these days?

FogerRox

(13,211 posts)
8. AFAICT a slightly larger size
Mon Jun 30, 2014, 07:39 PM
Jun 2014

Net power with proton boron11 fuel used to be 3 meters, it may be closer to 3.5 to 4.

Remember this paper is about a smaller machine than WB-8.

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