Monday, September 10, 2012

How It Works

How It Works:

A short YouTube Cartoon explaining how the Polywell works, is needed.  It has to be simple and informative.  Explaining the mechanism is really important.  Is there an animator that is willing to help?   Deciding on the right amount of detail will be hard.  We could almost make three videos with increasing levels of details.  However, for the general public a simple video will suffice.  Here is an example of what is needed.  Since this is still new idea, there may be changes to add later.  But, we need a movie out there now, so new Polywellers can quickly understand the mechanism.  Enumerated below are the nine purposed steps for Polywell fusion. 
1. ELECTRON EMITTED: The electron can be generated using thermionic emission [3, 21] from a metal surface.

2.  ELECTRON FALLS TOWARDS RINGS:  There is a voltage drop between the outside cage and the rings.  In WB6 this was 12,500 volts [4].  The electron is emitted some distance from the device.  The electron “falls” down the voltage drop towards the rings.  It moves this way because it is experiencing the electric component of the Lorentz force [5, 6].

3.  ELECTRON GETS CAUGHT BY RING FIELD:  When the electron gets close it starts to feel the magnetic fields.  Specifically, the magnetic component of the Lorentz force becomes stronger than the electric force [5].  The electron starts following the magnetic fields generated by the rings.  The electron oscillates around one of these magnetic field lines, following it towards the center, giving off cyclotron radiation [7].

4.  ELECTRON MOTION INSIDE CENTER:  When the electron reaches the center, its' motion becomes straighter as it passes through the null point [8].  This is the point of no magnetic fields in the middle of the rings.  As it heads out the other side, it starts oscillating again.  This oscillation get tighter as the electron gets farther away from the center [14, 11].  The radius of oscillation is the electron gyroradius [9].  The electron follows the magnetic field lines.  These lines are drawn together, tighter and tighter at the corners.  The magnetic field gets denser.  The electron oscillation gets smaller and tighter.  At some point, the field gets so tight that the electron hits a magnetic mirror at the cusps [9, 10, 11, 14].  The electron turns around.  It heads back toward device center and repeats the motion [11, 14].  An electron should be lost after a given period of time [11].

5.  ELECTRON CLOUD BEHAVIOR:  When a large number of electrons are inside the rings, they should appear as a pulsating swarm where material swirls around and moves forward and back to the cusps.  This electron motion generates mini magnetic fields [12].  It has been purposed [4]: that these mini fields resist the rings fields.  This is not proven.  This would be analogous to the electron cloud going diamagnetic [22, 23].  If this were true, the electrons may occupy spherical cloud in the center, with 14 “spikes” pointed towards the cusps along the 8 corners and the 6 sides.  If true, this may positively affect conduction losses.

6.  D2 GAS INJECTION: The D2 gas is puffed towards the rings [4].  This is the uncharged D2 gas.  This means that the gas is less affected by the electric fields.  Hence, it can make it to the edge of the rings.  Bussard puffed the gas in at the relatively high pressure of 3E-4 torr against vacuum pressure of 1E-7 torr [4].

7.  THE D2 IONIZES:  When the D2 reaches the edge of the rings it is hit by an electron.  If the electron is hotter than 16 eV [1] the D2 will become an ion.  Bussard estimated that the typical electron in his device had 2,500 eV [4] at the beta=1 condition [13].  This collision heats up the deuterium and it ionizes.   The deuterium loses an electron to become the ion.  The ion is positively charged and is attracted to the cloud of electrons in the center.  In WB-6, this attraction created a 10,000 volt drop for the ions to "fall down"[4].

8.  ION FALLS & COLLIDES: The charged deuterium is attracted to the electrons in the center.  It is attracted by the 10,000 volt drop.  It “falls down” this hill towards the center [4].  The ion builds up 10,000 eV as it falls.  Note that the deuterium ion is about 3,670 times more massive than the electron [16, 1].

9.  FUSION:  If two ions do collide at 10,000 eV, they can fuse.  The product will be have on the order of 1 MeV [19] of energy and cannot be held by the electric or magnetic fields.  It should therefore rapidly exit the rings.  As the voltage increases the odds of fusion typically improves.  This is measured by a fusion reactions' cross section [19].  The stated goal of NIF was to get the average plasma temperature over 10,000 eV under confinement [2].
Inside WB-6, the deuterium could have collided with 10,000 electron-volts of kinetic energy.  This would give a fusion cross section of 1E-4 Barns [19].  This cross section is entered into the volumetric fusion rate equation [20].  This equation is shown below with typical numbers for WB-6 [4, 24, 25].  The ion density is estimated from experimental estimates [4].  The equation predicts that 4E-9 Joules/second will emanate from the cloud.

Many other things can happen as the ions fall towards the device center.  The ion can interact with other electrons or ions.  They interact if the distance between these objects falls below the Debye screening length [17].   These interactions can create x-rays, repulsion or collision without fusion [18].  Three main criticisms against this idea are: x-rays sap away too much energy, the electron and ion temperature cannot vary more than 5% and a bell curve of ion energy keeps most of them too cold to fuse [18]. 
SCALE UP: What happens if the device is scaled up?  Listed here is the volumetric rate equation for better machines.  The first example is a machine fusing deuterium and tritium with a 64,000 volt drop.  If the fusing gas has the same density, then the equation predicts 0.003 joules per second will emanate from the cloud [25].

If the machine is fusing boron-11, then the reactor can exploit the fact that the boron has a charge of five.  Because of this, the boron experiences five times the Lorentz force for the same electric field [25].  This means that peak boron proton fusion may be possible with a much smaller voltage drop.  

Cross sections for different fusion reactions are shown below [19, 25].
1. “Deuterium." Deuterium. National Institute of Standards and Technology, 2011. Web. 06 Sept. 2012. .
2. "Development of the Indirect‐drive Approach to Inertial Confinement Fusion and the Target Physics Basis for Ignition and Gain." John Lindl.  Page: 3937.  AIP Physics of Plasma. American Institute of Physics, 14 June 1995.
3. Richardson, O. W. (2003). Thermionic Emission from Hot Bodies. Wexford College Press. pp. 196. ISBN 978-1-929148-10-3.
4. Bussard, Robert W. "The Advent of Clean Nuclear Fusion: Superperformance Space Power and Propulsion." 57th International Astronautical Congress (2006). Web.
5. Carr, Matthew, and Joe Khachan. "The Dependence of the Virtual Cathode in a Polywell™ on the Coil Current and Background Gas Pressure." Physics of Plasmas 17.5 (2010). American Institute of Physics, 24 May 2010. Web.
6.  Nave, R. "Magnetic Force." Magnetic Forces. N.p., n.d. Web. 01 Sept. 2012. .
7. Bornatici, M. "Electron Cyclotron Emission and Absorption in Fusion Plasmas." Nuclear Fusion 23.9 (1983): 1153-257. Print.
8. J. Berkowitz, K. Friedrichs, H. Goertzel, H. Grad, J. Killeen, and E. Rubin, Proceedings of the 2nd International Conference on Peaceful Uses of Atomic Energy (Geneva, Switzerland, 1958), Vol. 1, pp. 171–176.
9. F. Chen, Introduction to Plasma Physics and Controlled Fusion (Plenum, New York, 1984), Vol. 1, pp. 30–34.
10.  Fitzpatrick, Richard. "Magnetic Mirrors." Magnetic Mirrors. N.p., 31 Mar. 2011. Web. 06 Sept. 2012. .
11. Carr, Matthew, and David Gummersall. "Low Beta Confinement in a Polywell Modeled with Conventional Point Cusp Theories." Physics of Plasmas 18.112501 (2011): n. page. Print
12.  "Why Does Moving Electron Produce Magnetic Field?" Why Does Moving Electron Produce Magnetic Field? Physics Forums, 3 July 2007. Web. 24 Aug. 2012. .
13.  Correll, Don. "Plasma Dictionary." Plasma Dictionary. Lawrence Livermore National Laboratory, 12 July 2000. Web. 1 Sept. 2012. .
14. Mandre, Indrek. "Polywell Simulation 3D." YouTube. YouTube, 02 June 2007. Web. 06 Sept. 2012. .
15. Barrow, John D., 2002. The Constants of Nature: From Alpha to Omega--the Numbers That Encode the Deepest Secrets of the Universe. London: Vintage. ISBN 0-09-928647-5.
16. "Proton-to-electron Mass Ratio." Wikipedia. Wikimedia Foundation, 09 June 2012. Web. 01 Sept. 2012. .
17. Spencer, Ross L. "A Brief Introduction to Plasma Physics." A Brief Introduction to Plasma Physics. Brigham Young University, n.d. Web. 6 Sept. 2012. .
18. Rider, Todd H. "A General Critique of Inertial-electrostatic Confinement Fusion Systems." Physics of Plasmas 6.2 (1995): 1853-872. Print.
19. Jarvis, O. N. "Nuclear Fusion 4.7.4." Nuclear Fusion 4.7.4. National Physical Laboratory, 2011. Web. 30 Aug. 2012. .
20. Lawson, J. D. "Some Criteria for a Power Producing Thermonuclear Reactor." Proceedings of the Physical Society. Section B 70.1 (1957): 6-10. Print.
21. "View Movie." Electronics At Work : Free Download & Streaming : Internet Archive. N.p., n.d. Web. 06 Sept. 2012. .
22. Simon, Martin. "Diamagnetic Levitation." Diamagnetic Levitation. University of California Los Angeles, n.d. Web. 06 Sept. 2012. .
23. "Of Flying Frogs and Levitrons" by M.V.Berry and A.K.Geim, European Journal of Physics, v. 18, p. 307-313 (1997).
24.  Elert, Glenn. "Kinetic Energy." Kinetic Energy. The Physics Hypertextbook, n.d. Web. 10 Sept. 2012. .
25.  Atzeni, Stefano, and Jürgen Meyer-ter-Vehn. The Physics of Inertial Fusion: Beam Plasma Interaction, Hydrodynamics, Hot Dense Matter. Oxford: Clarendon, 2004. Print. Page 12



  2. This video has been around for a while and does a good job of explaining the basics:

    You should ask FogerRox if they created it and if you can use it.

  3. I think this adds more information to FoxRoger's video. He deserves respect. Nobody is getting paid yet to do this work. We are doing it because this idea is awesome.

  4. @The_Polywell_Guy
    I just suggeseted that video because at the top of the page you were asking for a video to include in this work. I agree that this page has more info.

  5. Congrats on Turning 3, Polywell Blog. I have been checking this blog. This site has good stuff on it. Keep up the good work.

  6. Now this may be a stupid question. But when the fusion occurs and everything works out as it should, how would you savely get the energy out of the polywell reactor?

  7. I don't know. There are going to be lots of problems that will need to be solved - and this blog cannot offer solutions to all of them.

    What is clear is this: the polywell can fuse atoms. It may be the cheapest, simplest and smallest machine in the world to pull this off. The machine is new and untested. Nobody can say what are its capabilities and limitations. We need more debate, scrutiny, and research.

    This reactor has staying power. This blog has been up for 3 years now. The forum has 360,000+ registered email addresses. We have polywell papers and books being written. We have an understanding of how it works. So far, we have seen a path forward. This may be the start of something big.

    It is also true that the whole world is racing to find new sources of energy. Every day energy supplies get tighter. Whoever gets this machine to work will change the world.

  8. Whatever dude, nice soap box.

    To answer your question alex, you can use thermal cycles if you are fusing DD or DT. You would run tubes around reactor which would absorb heat. The heat would make steam, and the steam would turn turbines.

    If your doing Proton-Boron fusion there is an idea called direct conversion. IDK allot about it but you are supposed to be able to decellerate ions against an electric field. It is supposed to be WAY more efficent.

  9. Here are two papers on direct conversion to get you started:

    - "Venetian-blind direct energy converter for fusion reactors” NUCLEAR FUSION 13 (1973) by R. W. MOIR, W. L. BARR

    - “Experimental Results from a beam direct converter at 100 kV” in the journal of fusion energy, Volume 2, Number 2, (1982) by R. W. MOIR, W. L. BARR.