Needed: A YouTube Cartoon For The Mechanism

Discuss how polywell fusion works; share theoretical questions and answers.

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mattman
Posts: 459
Joined: Tue May 27, 2008 11:14 pm

Needed: A YouTube Cartoon For The Mechanism

Post by mattman »

WANTED: AN ANIMATOR

We should to make a 2 minute YouTube Cartoon explaining the mechanism. It has to be simple and informative. Explaining the mechanism is really important. We should pay an animator to do a professional job. Deciding on the right amount of detail will be hard. In descriptions at least, I don’t mind getting really specific. But, in videos for everyone to watch, details will create confusion. Also I don’t think we have a full consensus on the mechanism. Since this is still a new idea, there may be changes still to make. But, if we can get a movie out there that then people can add to or argue with, that is good. Here is a first attempt. Am I forgetting something? Please chime in. The purposed physical steps for fusion in WB6 are:

1. ELECTRON EMITTED: The electron can be generated using thermionic emission [3], 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 falls 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. The magnetic component of the Lorentz force takes over. Oddly, the slower moving electrons are less likely to be caught by the magnetic field [7]. The electron starts riding the magnetic field of the rings. The electrons oscillate around one of these magnetic field lines, riding it towards the center. You could show the oscillating electron giving off cyclotron radiation [8] – aka – losing energy.



4. ELECTRON MOTION INSIDE CENTER: When it reaches the center, its motion becomes straighter as it passes through the null point [9] – the point of no magnetic fields in the dead middle of the rings. As it heads out the other side it starts oscillating again. This oscillation get tighter as it gets farther away from ring center [13, 17]. The radius of oscillation is the electron gyroradius [12]. The electron follows the field lines. These lines are drawn together, tighter and tighter at the corners. The magnetic field gets denser. The electron oscillation gets smaller, tighter. At some point the field gets so tight that the electron hits a magnetic mirror [10, 11, 7]. This is the cusps[13]. It turns around, heading back toward device center, repeating the motion.



5. ELECTRON CLOUD BEHAVIOR: You will need to cut to a cloud of moving charge inside the rings. This would be tons of electrons, so a blue cloud which cannot be seen through might be an appropriate visual. I imagine a pulsating swarming cloud where material swirls around and moves forward and back the cusps. The cloud would most likely occupy a spherical ball in the center, with 14 “spikes”, shooting out towards the 8 corners and 6 sides. This assumes the motion of the electrons creates their own mini magnetic fields [14] which resist the rings fields – forming a spherical pocket where the electron cloud can sit (this is not fully proven).



6. D2 GAS INJECTION: The D2 gas is puffed towards the rings [4]. Note: this is not the ion. It is the uncharged D2 gas. This means it is not affected by the electric fields. Hence, it can make it to the edge of the rings with no problems. 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, an electron hits it. This probably means the puffers are placed along the corners, or cusps [13], of the device. These electrons are occupying a dense magnetic field. That means they are in a spot of high potential energy. That means they probably have a low kinetic energy. However, if the energy is higher than 16 eV [1] ionization will happen. Since Bussard estimated the typical electron his device had 2,500 eV [4] at the beta=1 condition [16], this is plausible. This heats up the deuterium. It kicks off an electron and becomes an ion. The D2 is now a charged ion, sitting at the edge of the rings, facing a 10,000 voltage drop [4].



8. ION FALLS & COLLIDES: The charged deuterium is attracted to the electron cloud in the center. It is attracted by the 10,000 voltage drop, so it “falls down” this hill towards the center [4]. The ion builds up 10,000 eV as it falls. The Deuterium isotope is about 3,670 times more massive than the electron [18, 19].



9. FUSION: If a collision between two ions happen, they can fuse. This could mean two ions hitting head on, each with 5,000 eV. If the ions have a collective kinetic energy of over 10,000 eV, the DD fusion cross section is 1E-4 Barns [22]. This means that fusion can occur. The stated goal of NIF was to get the average plasma temperature to 10,000 eV under a dense confinement [2]. A head on collision may be best; hence placing the D2 puffers on opposite corners of the rings may improve performance. 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 [20]. These interactions can create x-rays, columbic repulsion or collision without fusion [21]. Three main criticism 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 [21].


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Citations:

1. http://webbook.nist.gov/cgi/cbook.cgi?I ... 90&Mask=20

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

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. http://hyperphysics.phy-astr.gsu.edu/hb ... agfor.html

7. http://thepolywellblog.blogspot.com/201 ... sults.html See Appendix.

8. http://en.wikipedia.org/wiki/Cyclotron_radiation

9. 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.

10. F. Chen, Introduction to Plasma Physics and Controlled Fusion (Plenum, New York, 1984), Vol. 1, pp. 30–34.

11. http://farside.ph.utexas.edu/teaching/p ... ode21.html

12. http://en.wikipedia.org/wiki/Gyroradius

13. http://webbook.nist.gov/cgi/cbook.cgi?I ... 90&Mask=20

14. 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.

15. http://www.physicsforums.com/showthread.php?t=184619

16. http://en.wikipedia.org/wiki/Beta_(plasma_physics)

17. http://www.youtube.com/watch?v=ao0Erhsnor4

18. http://en.wikipedia.org/wiki/Electron

19. http://en.wikipedia.org/wiki/Deuterium

20. http://en.wikipedia.org/wiki/Debye_length

21. Rider, Todd H. "A General Critique of Inertial-electrostatic Confinement Fusion Systems." Physics of Plasmas 6.2 (1995): 1853-872. Print.

22. http://www.kayelaby.npl.co.uk/atomic_an ... 4_7_4.html

mattman
Posts: 459
Joined: Tue May 27, 2008 11:14 pm

Post by mattman »

I am working on refining this. Two points:

1. Kiteman says the electrons at the edge have a low potential energy.

2. The cross section is entered into the following equation**

Power From Fusion/ Volume = Number Density of Deterium^2 * Cross Section * Relative Velocity of Collision * Energy from 1 Reaction.

I wanna model two D2 ions hitting each other, each have 5,000 eV of kinetic energy and hitting head on. If the kinetic energy = 0.5*Mass*Velocity^2, then you can find the D2 velocity. This would yeild a plot of power/volume verses the density of the D2.





** Lawson, J. D. "Some Criteria for a Power Producing Thermonuclear Reactor." Proceedings of the Physical Society. Section B 70.1 (1957): 6-10. Print.

GIThruster
Posts: 4686
Joined: Tue May 25, 2010 8:17 pm

Post by GIThruster »

Why exactly should we pay someone to do a professional quality animation when EMC2 already has adequate funding and has for years, and when it is our tax dollars at work, and subject to FIOA, but the details are not being released to us?
"Courage is not just a virtue, but the form of every virtue at the testing point." C. S. Lewis

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