Positive Electrostatic Fusion Reactor

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Royce Jones
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Positive Electrostatic Fusion Reactor

Post by Royce Jones » Fri Aug 28, 2015 3:01 pm

Many in the fusion community is just now coming to the conclusion that in order to get higher fusion rates you have to focus on the ions rather than the electrons. This is true of all machines including Fusors, Polywells, Tokamaks, etc. This is called “new theory”, yet fusion has always been about combining nucleons. Electrons play no direct role in nuclear fusion they are only a control mechanism due to their opposite electrical charge, yet they add many instability problems to the mix. Using positive electrostatics you can obtain the same control while removing the problems related to electrons.

It is entirely possible to design a reactor that uses only positively charged ions. Such a reactor would remove all the problems associated with heating, maintaining, recharging and controlling electrons. The positively charged ions can be compressed in a reactor by giving the reactor a high positive charge. Additionally, the ions can be given directional control and compression using electrostatic fields. The proposed reactor design confines the ions, gives them directional movement in only two directions, and compresses the ions together at speeds that overcome the electrostatic repulsive force of the ions. Explained in simple terms, the reactor divides the ions into two groups, and then slams the two groups together at high speed. This process is controlled by relatively low energy electrostatics and is repeated millions of times per second. Since hydrogen ion collisions are critical to reaching higher levels of fusion the density of the ion cloud is very important. A large number of ions in as close proximity to each other as possible will create more opportunities for fusion reactions. This is a perfect scenario for fusion generation. This concept is called the Positive Electrostatic Fusion Reactor (PEFR).

The Positive Electrostatic Fusion Reactor plasma reactor is a simple electrostatic fusion device. However, it is substantially different from other electrostatic devices because it only uses positively charged ions. In conventional electrostatic fusion reactors the electrons are used to attract the ions toward the center or area of confinement. Electrons are not used by this reactor as they present substantial energy loss mechanisms, do not cause fusion and more importantly are unnecessary due to the design. The electrons can be removed from the plasma before the plasma enters the reactor.

The Positive Electrostatic Fusion Reactor uses electrostatic energy in two ways, first as a confinement mechanism and secondly as a pumping mechanism to pump energy and direction into the ions. In the Positive Electrostatic Fusion Reactor the confinement shell has a large positive electric charge which keeps the ions positioned away from the reactor wall and centered in the reactor chamber. Since the wall has a high positive charge the positively charged ions (protons) will be repelled away from the wall back into the plasma or ion cloud. There are several potential ways to control the ion (proton) pumping action using electrostatics to create fusion, however the simplest solution appears to be a simple cylinder with electrostatic plates at each end. This would be a delicate balancing act between electrostatic forces.

The reactor end plates can attract protons which have a positive charge by having a negative charge then switch to a positive charge to repel the protons back to the center. In this case no electrons are needed. Since using electrons can add to energy losses, this may be the best approach. However, the magnetic energy density required to confine electrons is far smaller than that required to directly confine ions. This is overcome using electrostatic forces. The wall has a positive charge and the plates can switch between positive and negative charges.

In the picture (figure 1) above the basic positive electrostatic fusion process is shown. The ions in the plasma are attracted to the end plates that have a strong negative charge. When the charge is switched to positive the positively charge ions are repelled back to the center at high velocity where they will impact with ions returning from the opposite side. When two D-D or D-T ions collide at sufficient speed fusion will take place.
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PUMP2.png
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Dan Tibbets
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Re: Positive Electrostatic Fusion Reactor

Post by Dan Tibbets » Sat Aug 29, 2015 7:17 am

A positive ion only fusion reactor is a nonstarter. You cannot have a pure positive charged ion plasma in any density that produces more that tiny amounts of fusion.
Read further at your own risk :)

First off, bouncing ions back and forth between two end plate electrodes by timing polarity reversals is a difficult proposition. A ion population with monoenergetic energy distribution would be required, thermalization due to interparticle collisions would result in a mixture of energies. To prevent up scattered ions from reaching the plates, the management of the potentials probably need to far exceed the average kinetic energy of the ions- ie- the potential well would be shallow relative to the applied voltages. Timing would be critical. Some type of resonance might help, but managing losses while providing adequate KE to the ions would be a challenge. Then there are the ions that are scattered sideways, how are they contained? Gauss Law considerations may apply unfavorably also..

The major criticism though is based on the Coulomb repulsion or attraction between charged particles. This Coulomb repulsion/pressure rises exponentially with density. The Brillion Limit would apply (I think). Basically this is a consequence of inter particle repulsion. A density of at most ~ 10^13 unbalanced charges/ cubic centimeter is manageable. Anything more will fly apart and could only be contained by applying rapidly increasing electrostatic fields (millions and then billions of volts). As a rough example, a potential of perhaps 10,000 volts may constrain a pure ion population of perhaps 10^17 per cubic meter. To increase the pure ion density to useful levels so that reasonable amounts of fusions could occur per second, you need somewhere around 10^18 ions per cubic meter or higher . This might give you a few megawatts of power in a ITER sized machine. This would not come close to matching the input power. Even if you could somehow get excess power it would only be enough to power a small village, at a construction cost of billions and billions of dollars. Because of this tremendous Coulomb pressure that grows with UNBALANCED plasmas, you have to have electrons and positively charged ions in the system. Negatively charged ions would add interesting conditions, but I am aware of no claims of maintaining negatively charged ions in more than tiny amounts in a plasma. A plasma does not have to be neutral with equal negative and positive charges, but it cannot vary by much. The Polywell takes advantage of a non neutral plasma with an excess of electrons but the imbalance is only about one part per million. With a particle density of perhaps 10^20 particles per cubic meter, this represents 0.5000001 *10^20 electrons and 0.4999999*10^20 positive ion charges per cubic meter. The difference is not much. Both electrons and ions have to be present in any plasma where useful amounts of fusion can occur. Or with a total charged particle density of 10^20 particles/ cubic meter, the electron excess would be 10^14 electrons per cubic meter, or 10^8 electrons per cc. This imbalance is tolorable and actually useful in the Polywell scheme. It creates the potential well- virtual cathode that contains the ions. The electrons are adequately contained by the magnetic fields (at least that is the goal).

A penning trap with electrostatic electrodes might be built to contain antiprotons or other charged particles, The key here is that the densities are tremendously below the Brillion limit. Possibly only a few million particles per cubic meter.

Some further discourse on unbalanced +/- charges in a plasma is discussed in this thread on the Talk Polywell forum. It is hopefully not too confusing or misleading. It does represent my understanding of the issue of tolerable and desired charge imbalance in a useful fusion plasma.

http://www.talk-polywell.org/bb/viewtop ... f=3&t=5778

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Frank Sanns
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Re: Positive Electrostatic Fusion Reactor

Post by Frank Sanns » Mon Aug 31, 2015 12:20 pm

Royce,

The image that you posted is corrupted so we cannot see your drawing. Would you mind reposting the image. I have some thoughts on the matter but want to be sure I fully understand what you are proposing.

Thanks.

Royce Jones
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Re: Positive Electrostatic Fusion Reactor

Post by Royce Jones » Mon Aug 31, 2015 4:01 pm

Repulsive charge of the ions in the beam is not a problem because like charges moving in the same direction are actually attractive rather than repulsive. This only becomes a problem when the ions slow down or stop and even this can be used to advantage by allowing the ions to expand without the use of a negative charge so that the next pulse can slam them into each other.

SPACE-CHARGE NEUTRALIZATION
The density of electrons in a broad ion beam is approximately equal to the density of ions. In plasma physics this is called
“space-charge neutralization” or “quasi-neutrality.” As an example, consider a long, cylindrical beam of 500 eV
ions, 10 cm in diameter and with a current density of 1 mA/cm2. If no electrons were present, the potential difference
between the axis and the outside surface of the beam would be over 14,000 V. Adding "space-charge neutralization" would only disrupt the beam so it is something to be avoided not something you are looking to instill into the operation.

The problem is the potential for arching to the chamber wall. This can be controlled by a positive charge on the chamber wall. The charge will also help contain the beam while the pulse instills directional control. Therefore, no magnetic compression is required. Timing would be critical to operation. Not sure what went wrong with the picture, I will create a new one and post it.

Royce Jones
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Re: Positive Electrostatic Fusion Reactor

Post by Royce Jones » Mon Aug 31, 2015 4:44 pm

Pulse.png
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Frank Sanns
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Re: Positive Electrostatic Fusion Reactor

Post by Frank Sanns » Mon Aug 31, 2015 7:33 pm

I do not think the configuration that you are proposing will work as you propose. Putting high negative potential on parallel plates will not be the same as a high negative potential in the middle.

I ran some experiments to test this with concentric inner grids well inside of the vacuum chamber. I ran a high negative potential on the inner grid and grounded the outer grid. This is the typical fusor configuration and it works. Of course it works or we would not be on this site. Then I ran a high positive potential on the outer grid and grounded the inner grid. Since charge is a relative phenomenon, the situations should have yielded the same result. In both cases, the outer grid was 35kv more positive than the inner grid. In the configuration where the inner grid was grounded and the outer grid was at +35kv potential, there was essentially zero fusion.

Clearly the configuration has and impact on it since it cannot be the potential or the polarity. Indeed it is due to Gauss's law. For a sphere, the charge is on the surface of the sphere and the electric field is zero inside. Two parallel plates are like two portions of a complete sphere. While the maths are slightly different, the result is the same. Two close plates with the same potential put on them will not have an electric field between them. They are at the same potential and the charge will be on the outside faces of the plates.

Of course if the plates are far apart so as to not affect each other, ions could be accelerated towards each other but that is a collider. A compressor from close plates is not going to work for the reasons stated. Not trying to be a pessimist here but the theory says that and so do my own experimental results.

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Re: Positive Electrostatic Fusion Reactor

Post by David Kunkle » Mon Aug 31, 2015 11:24 pm

That would make one helluva physics test question:
Frank Sanns wrote:I ran a high negative potential on the inner grid and grounded the outer grid. This is the typical fusor configuration and it works. Of course it works or we would not be on this site. Then I ran a high positive potential on the outer grid and grounded the inner grid. Since charge is a relative phenomenon, the situations should have yielded the same result. In both cases, the outer grid was 35kv more positive than the inner grid. In the configuration where the inner grid was grounded and the outer grid was at +35kv potential, there was essentially zero fusion.
Explain for 50 points.

Electrons on the inner grid should see no + charge on the outer grid, and therefore, there should be no amperage and there wouldn't even be plasma let alone fusion in the reversed setup- right?

Not to pile on Royce, but since he plans on using a + charged chamber to keep stray ions away from the walls, Gauss' Law strikes again, doesn't it? The ions wouldn't see any + charge on that cylindrical outer chamber.

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Garrett Young
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Re: Positive Electrostatic Fusion Reactor

Post by Garrett Young » Tue Sep 01, 2015 2:14 am

Frank Sanns wrote:I ran some experiments to test this with concentric inner grids well inside of the vacuum chamber. I ran a high negative potential on the inner grid and grounded the outer grid. This is the typical fusor configuration and it works. Of course it works or we would not be on this site. Then I ran a high positive potential on the outer grid and grounded the inner grid. Since charge is a relative phenomenon, the situations should have yielded the same result. In both cases, the outer grid was 35kv more positive than the inner grid. In the configuration where the inner grid was grounded and the outer grid was at +35kv potential, there was essentially zero fusion.
The question is what was the potential of the vacuum vessel? Take a look at the following electrostatic simulations:

+35KV outer grid with grounded inner grid and vacuum vessel
PosOuterGrid.png
Very low fusion rates in this configuration isn't surprising given that there isn't a central focus for acceleration.



-35KV inner grid with grounded outer grid and vacuum vessel
NegInnerGrid.png
Typical Fusor arrangement



+35KV outer grid, grounded inner grid, and FLOATING vacuum vessel
PosOuterGrid-floatingshell.png
Although this wouldn't be a safe configuration, the electric field vectors are virtually identical to the typical Fusor arrangement and I would bet that similar fusion rates would occur.

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Frank Sanns
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Re: Positive Electrostatic Fusion Reactor

Post by Frank Sanns » Tue Sep 01, 2015 2:32 am

The outer chamber was insulated so it effectively out of the equation. Also the distance between my outer grid and the chamber is larger than the distance to the inner grid.

Here are some links to pictures of my fusor and work and the discussions:

viewtopic.php?f=18&t=7807

viewtopic.php?f=18&t=7844

viewtopic.php?f=18&t=7843

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Garrett Young
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Re: Positive Electrostatic Fusion Reactor

Post by Garrett Young » Tue Sep 01, 2015 2:54 am

+35kV outer grid and grounded inner grid inside a pyrex bowl. The chamber is spaced at a larger distance ratio and grounded.
PosOuterGrid-GlassBowl-LargeRatio.png
Frank Sanns wrote:The outer chamber was insulated so it effectively out of the equation.
I would respectfully disagree.

The pyrex bowl is modeled in this simulation and of course it effects the electric field (as any dielectric would) but the field lines still extend radially and diffuse the acceleration focus. I think floating the chamber (and eliminating the glass bowl for ion re-circulation purposes) would have increased the fusion rate.

Garrett
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