Can we contain the electrons only with the Magnetic field?

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

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hanelyp
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Joined: Fri Oct 26, 2007 8:50 pm

Re: Can we contain the electrons only with the Magnetic fiel

Post by hanelyp »

Mattman, those look like magnetic fields from just the coils, without the contribution from the plasma.
The daylight is uncomfortably bright for eyes so long in the dark.

KitemanSA
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Joined: Sun Sep 28, 2008 3:05 pm
Location: OlyPen WA

Re: Can we contain the electrons only with the Magnetic fiel

Post by KitemanSA »

hanelyp wrote:Mattman, those look like magnetic fields from just the coils, without the contribution from the plasma.
Concur.

D Tibbets
Posts: 2775
Joined: Thu Jun 26, 2008 6:52 am

Re: Can we contain the electrons only with the Magnetic fiel

Post by D Tibbets »

I admit to some confusion about your energy inputs. The only real energy input is the electron current and voltage. There is essentially no ion input energy as they are placed inside the machine at almost zero KE . The magnetic field energies are also near zero if superconducting coils are conviently assumed (just like with Tokamaks).

The two critical e3lements is the electron magnetic confinement under Wiffleball conditions. This is generally considered to be ~ 10,000 passes or recirculations, cyclic current. If there was no recirculating current/ confinement the input current would need to be ~ 10,000 times greater to maintain the same populqation of electrons inside the machine. Added to this is the Recirculation of ~ 90% of the electrons that do escape magnetic confinement. Thus the ~ 100,000 multiplication of the electron current that allows for expectations of positive fusion power out versus the input (electron current * voltage) power.
The magnetic fields do not directly effect the energy balence. B fields only change the direction of charged particles, not their energy. All sorts of arguments about thermalization, annealing, degree of radial vectors vs angular momentum, confluence, etc. then enter the picture. But they are all secondary to this primary concern about viability. Also keep in mind that in the ideal case, the vast majority of ions do not interact with the magnetic field at all, they all (except for upscattered ions not renormalized by annealing) spend their lifetime in the purely electrostatic domain.

As for models, peruse the EMC papers as several models are described to an uncertain extent. Also digesting the differences between Riders and Nevins (?) models and Dolan's model* is necessary to resolve assumptions.

Finally, any of these models are approximations that are simplified in order to allow for computational results within out lifetimes. And, always actual experimental results always trumps models. As these expiremental results are closely held with only partial teasers publicly available, the speculation continues.

*"Review Article: Magnetic Electrostatic
Plasma Confinement" Look on the Askmar site.

Dan Tibbets
To error is human... and I'm very human.

D Tibbets
Posts: 2775
Joined: Thu Jun 26, 2008 6:52 am

Re: Can we contain the electrons only with the Magnetic fiel

Post by D Tibbets »

A clarification- current recirculation / cyclic current due to the Wiffleball cusp magnetic electron confinement is separate from the "Recirculation" of magnetic confinement lost electrons.

An analogy might serve. Consider the Wiffleball confinement like an 'almost superconducter'. The current cycles repeatedly with only a small fraction of the loss of energy such as seen in a copper wire. That small loss results in energy leaving the system, consider this as heat . By using a steam cycle, you might recover ~ 30% of this lost energy/ heat and convert it into reusable electrical energy. Recycling of magnetic confinement loss electrons through Recirculation is essentially the same result, except that the recovery efficiency may be closer to 90%.

I like to think that this quoted 90% efficiency may actually be a conservative estimate. Nebel's comments about WB 7.0 heating of the nubs, and hinted changes to WB7.1 and then WB8 may allow for higher recovery efficiency. This suggests a small to modest gain over the baseline WB6 data may be significant when scaling to larger and more powerful machines If WB 6 at the test conditions produced 1 mW of fusion power with ~ 500 KW of power in, then the Q under this baseline comparison condition was ~ 0.000000002. If WB7.1 achieved the same fusion rate, but at 100,000 W input then , the Q was ~ 0.00000001 . This 5 fold gain would have profound implications on the scaling, especially with P-B11 fusion where the optimistic Q is only ~ 5-20, based (I presume) on WB6 data.

Dan Tibbets
To error is human... and I'm very human.

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