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Fusor without inner grid?

Posted: Mon Jan 30, 2017 5:49 am
by Rinze Joustra
To find this out I've made a computer program to simulate the movement of charged particles in an electric and magnetic field (in vacuum).
Coulomb's law, Biot-Savart formulism and Leapfrog integration is used (non-relativistic).

First I came across a configuration that confines only positive ions (or electrons). But I discovered that this was quite similar to the already existing Penning trap and would not be very effective to produce fusion, because of the nonneutrality of Penning trap plasmas.

Then I changed it a bit and now it's possible to trap both positive deuterium ions and electrons. The design just needs a constant magnetic field of about 1 tesla and a couple of rings and small spheres with a voltage of about +/- 200 kV. Depending of the polarity of the rings & spheres, there are two possible configurations. The ions and electrons are generated in the program with random speeds up to 3E6 m/s in all directions (and still keep confined).

But.., this is only a simulation with very few particles (no more than 500 or 1000), the simulation time is very small and it doesn't prove that any fusion would take place..

If you are interested:

http://www.valgetal.com/physics/Droomid ... g.%206.jpg (1e configuration)
http://www.valgetal.com/physics/Droomid ... 0fig.7.jpg (2e configuration)
http://www.valgetal.com/physics/Droomid ... oom11.html (calculations, screenshots etc.)
https://www.youtube.com/watch?v=bvvv1YLbuLY&t=11s (video capture of a simulation)

Thank you for your time and regards

Re: Fusor without inner grid?

Posted: Mon Jan 30, 2017 7:46 am
by Dan Knapp
Interesting results. What you have modeled is a variation on the Malmberg-Penning particle trap. The fly in the ointment would be actually building a device and maintaining 400 kV standoff in the presence of a conductive plasma. If you're interested in pursuing the subject further, you need to do a literature search to learn what has already been done. For example, there is extensive literature on the Penning trap as a fusion reactor, and theory predicts that it could even produce net energy (google D. Barnes and D. Nebel). Practical realization has the same problem with high voltage standoff, and no one has yet actually done fusion in a Penning trap. Your conclusion that it wouldn't work because the plasma is non-neutral is incorrect; that is precisely how it does work in theory. You should also read about the polywell, another gridless fusion device that uses electric and magnetic fields (google Park, and there are entire web sites devoted to the Polywell). Finally, there is one paper in the literature on the planar fusion reactor, a much simpler design of a gridless IEC device that does not use a magnetic field (google D. Knapp). So far this design has also only been modeled. Keep modeling! That's how new designs will be found!

Re: Fusor without inner grid?

Posted: Mon Feb 06, 2017 3:02 am
by Rinze Joustra
Thank you for your constructive reply!

Yes, I will continue, although the coming period I will be very busy to make a living.

By the way, perhaps I gave the particles in the simulation an excessive high initial speed. With an initial speed up to 1E6 m/s they stay confined with “only” +/- 80 kV and with a magnetic field of 0.6 tesla. See the attached picture.

The electrons are a lot easier to trap, because of their small mass. In the shown configuration they stay close to the centre, where they could form a virtual cathode (reading about fusion with Penning traps, I’ve understood that this has already been studied and tried out).

By placing the positive charges on top and down under, the D+ ions are confined by the external B and E-field and will be attracted (I suppose) by the electron cloud in the centre.

Regards

Re: Fusor without inner grid?

Posted: Fri Feb 10, 2017 7:14 am
by Dennis P Brown
I would say a
magnetic field of 0.6 tesla
is one strong field! The trick, of course, is sealing such a "bottle" and this standard mirror design has never worked very well when used in the 60's/70's and were abandoned for that reason. Also, producing 0.6 Tesla field over any standard fusor is a task requiring massive magnets - a 40 cm gap is rather huge for such a field. Maybe super conductors would work in this case but that is a bit over what most amateur's have access to ...I would think. ;)

Re: Fusor without inner grid?

Posted: Fri Aug 11, 2017 7:00 am
by Rinze Joustra
A little late reply...

The "SEM fusor" design is not a standard mirror or magnetic bottle. The rings are charged (no current!) and generate a static electric field which confine the particles ( deuterium ions and electrons) in the vertical direction. The magnetic field is static as well (and uniform) and confine the particles in the sideward direction.

But to try out and test my simulation program I programmed some current rings to simulate such a magnetic bottle. The result was that a part of the deuterium ions stayed more or less confined, but also that a part of them escaped.
So indeed the magnetic mirror does not seem to work very well; the SEM fusor works better, anyway in the computer simulation.
( see https://www.youtube.com/watch?v=Ya58Fn9Jq0w )

A magnetic field of about 1,5 tesla is quite strong, but a lot smaller than the one used by, for example, ITER.
Perhaps a MRI scanner of a hospital can be used. They use superconducting magnets cooled by liquid helium, with a field strength of 1,5 till 3 tesla, and according my information, are switched on all the time. At the moment I am initiating contacts (positive so far ..).

Then only is needed a vacuum chamber, with a little bit deuterium gas, a couple of rings and spheres and a power supply (although the required voltage is a bit high, but possible I assume). Everything of course of non-magnetic material: glass and aluminium perhaps, otherwise the experimental device would be damaged when introduced inside the scanner... And of course a neutron detector.

I do not pretend to have invented THE fusion device. What I have is a simulation program and with relative simple calculations with Coulomb's law , Biot-Savart formulism, a good integration method and "reasonable" values for the magnetic field and the voltages it confines both deterium ions and electrons up to speeds of 3,5 E6 m/s, which is higher than the mean speed needed for fusion (= 2 E6 m/s according my information).

A shortcoming of the simulation program is that it can only simulate a couple of 100 particles. What would happen with millions and millions of them, in a real experiment?

Recordings of my simulation experiments are available in the internet, as well as my calculations.

Best regards
:)

Re: Fusor without inner grid?

Posted: Fri Aug 11, 2017 10:51 pm
by David Kunkle
I hope you can get access to an MRI. Would certainly be cool to try it out, but I will be surprised if anyone allows your experiment. Did you actually talk to anyone that has direct authority over the scanners? Because...

"Everything of course of non-magnetic material: glass and aluminium perhaps, otherwise the experimental device would be damaged when introduced inside the scanner... And of course a neutron detector."
That is probably only the start of your problems. They will not allow anything ferromagnetic in the entire scanner room. Not so much as a paper clip. That would probably leave out most HVPS's, bottles of deuterium, neutron detectors (except bubble detectors), and vacuum gauges and pumps (especially roughing pumps).
MRI gone wrong.jpg
These two guys were badly injured when the doctor asked for an oxygen "mask", but one of these guys thought the doctor said oxygen "tank". When the emergency shut down/venting failed, they tied a rope around the cylinder, and 20 people couldn't pull it off the magnet.

This is pretty interesting- especially if you read all the way to the bottom about what can go wrong when you bring ferromagnetic materials into the room. It's also very expensive to re-start an MRI when someone screws up by bringing the wrong kind of metal into the room. http://www.bic.ucsb.edu/forms/MRIroomSafety.pdf
Like I said, I'd be surprised if anyone in charge allows this. At the very least, you'd need some very long wires, cables and tubing to keep most of your equipment outside the scanner room.

"What would happen with millions and millions of them, in a real experiment?"
Probably more like at least billions and trillions vs. a few hundred in simulation. The containment wouldn't be anywhere as neat and tidy as in the simulation.

Re: Fusor without inner grid?

Posted: Fri Aug 11, 2017 11:51 pm
by Richard Hull
Of course, this being the theory section, lots of "modeling", yet, no one will do anything about anything. No experiment will be done and nothing will come of the idea. As always, armchair exellence shines as brightly as ever. Interesting ideas, no physical embodiment, no experimentation.

Richard Hull

Re: Fusor without inner grid?

Posted: Tue Dec 12, 2017 8:46 pm
by John Fenley
This is very similar to what I am working on, and it does seem very similar to a Penning trap. I've done some simulations, and gotten some promising results.
https://www.youtube.com/watch?v=RT6nvmN7GB0

I've looked at buying a cheap MRI machine that will supply the magnetic field. The one I've been looking at is the Airis II with a .35T permanent magnetic field. They cost from $30k-$120k. Without that, very few tests are able to be done. I haven't been working in a "vacuum" though, I've worked with several others that have made IEC fusors, and worked on high vacuum, and high voltage systems. At least for now, the limiting factor is access to the magnetic field.

I have more information on http://www.DDproFusion.com, including our published patent application. When we get some money, we'll actually start building :)

Re: Fusor without inner grid?

Posted: Wed Dec 13, 2017 5:42 am
by Dennis P Brown
Your overwhelming mistake like everyone who desire to produce net energy with fusors is you believe the issue for getting net energy from these devices is something that can be fixed. It simply is not possible due to the nature of how fusion occurs in fusors. Like the Sun, the process solely depends on tunneling - you can't increase tunneling (if you could, then we have something that might be possible.) You can waste your money and build a virtual grid (Like the Pollywell - which also is useless for net energy) but if you depend on tunneling, you can never get net energy.

A fusor will never generate more energy than you put in under any methodology available here on Earth (short of using 'free' gravitational pressure like the Sun does.) You can't over rule reality - a fusor with no grid, or a virtual grid, or a real grid simply does not matter - tunneling is not a viable energy source and never will be using magnetic fields or electric fields for confinement.

Your simplistic simulations on a home computer are just very rough approximations (and extremely poor ones) to the reality of a plasma. Believing any such results is not a sound idea. You are not actually modeling the complex interactions of real ions and electrons in an electric field except in a very rough manner. Even super computers run by many PhD physicist that have devoted their entire careers in such modeling even consider that their efforts are just approximations and fail to capture all the critical information of reality and would never believe their results are so good that any device so designed will then work as modeled.

You are, maybe, confusing the process used in the big machines of physics with fusors - these monster devices use shear kinetic energy to force deuterium/tritium through the Coulomb barrier; these machines (Stellarators, Tokamak's, mirror machines, etc) do not use tunneling; in theory, KE methods could produce net energy but to date, that method has not been successful (and we all know, net energy still has not been achieved (but they are, at least, close to that trivial goal.)) Also, increasing the magnetic field, even for KE devices, fails. The issue is stability in the plasma for KE devices (again, which a fusor definitely is not.)

Re: Fusor without inner grid?

Posted: Wed Dec 13, 2017 6:37 pm
by John Fenley
I'm going to agree with you that a simple fusor is a dead end energy wise. Short summary: Grid collisions, a growing cool clump of ions, and only a single chance to accelerate each new ion ensure that it's not going to be sustainable. That's why, at least in my device, I'm trying to create an environment where energy loss is minimized... Energy goes in, it doesn't come out. I ring it like a wine glass at it's harmonic frequency and eventually, something has to give. My hope is that what gives is the coulomb barrier. The energy of the ions in this style of device can go as high as desired.

I understand the tunneling issue.That's why each ion gets as many chances to tunnel as possible. It's periodic. I think this design could maintain Ions at high energy, with low losses, for as long as required to fuse.

I'm sure I don't have the full story. I'm sure unexpected issues will arise. Here's a simulation that shows what has been identified as a diocotron instability, but I think I have a solution: https://www.youtube.com/watch?v=NnbfgTP7v5M


I welcome actual analysis that might lead me to a better understanding. I even hope you can poke a good theoretical hole in this thing before I go spending hundreds of thousands of dollars building a prototype.

Most of what I do is gedanken, but to me, this design seems better than any other device I've seen.

Re: Fusor without inner grid?

Posted: Thu Dec 14, 2017 5:58 am
by Dennis P Brown
Well, trapping ions so that they do not lose energy is not unlike holding water in a ball of rubber bands - gonna leak badly. This ignores Bremsstrahlung loses, which for any significantly energetic electron is extremely severe and robs the plasma of energy no matter how perfect your magnetic/electro-static bottle because, you trapped them! The very goal you desire robs your plasma of energy.

OK, lets assume that your plasma 'leakage' is low (zero) and other loses are minimized (again, zero) so your containment energy cost is near zero and few ions lose energy by Bremsstrahlug (again, zero - all impossible but use this as the best case since it is); now, calculate how many ions achieve fusion via tunneling per sec in your 10 -100 micron gas; then calculate the energy so obtained from these fusion events (hint - many orders of magnitude lower than the 250 watts that a cubic meter of the Sun's ultra dense and super hot core releases every second) - in other words, if you were 100% perfect you're gonna get maybe 10^-3 watts per second for a cubic meter of plasma! Think this out - that assumes essentially zero losses and near 100% conversion of all possible tunneling captures per sec resulting in less energy production than a flashlight bulb yields in radiated energy/sec.

I could point out your claim that you get sufficiently low leakage out the ends that your net energy loss is less than fusion produces because you say so is not proof - as to why it will leak terribly and not trap your ions as you think can be shown by reading some of the vast scientific literature on mirror machines in fusion and their issues.

By the way, that is why tokamaks and stellarators were built - the ends are connected allowing the trapped ions to circulate as long as the plasma is stable (why that is not true for times past a few seconds isn't the point. Energy produced per sec tells us all we need to know.) In these devices, fusion via tunneling is essentially nil. So, why would yours produce more energy?

Re: Fusor without inner grid?

Posted: Thu Dec 14, 2017 7:48 am
by Dan Knapp
In the area of fusion, like many areas of science, there is not much really new under the sun. It is unfortunate that so many of the people with a “new” idea are unemcumbered by prior work. The “Fenley fusor” looks a lot like the “periodically oscillating plasma sphere (POPS)” that was studied extensively by the Los Alamos group twenty years ago. One can no longer claim lack of access to the scientific literature as an excuse. A little time googling can save one the embarrassment of reinventing the wheel.

Re: Fusor without inner grid?

Posted: Thu Dec 14, 2017 12:32 pm
by John Fenley
I have looked at POPs, and I've also looked at "Beyond the Brillouin limit with the Penning Fusion Experiment" also by the same group.
Pops tried to oscillate a sphere, my device oscillates a cylinder. The cyclotron is a very well known, cylindrical, periodic system capable of reaching the desired energies. Each ion in my device follows a cyclotron trajectory but is excited by an ion beam, not Ds, forcing each trajectory to pass through the same point at the same time, rather than circle the same point at the same time.

Here is small excerpt from the PFX paper: "It was suggested recently that the local density might exceed n in a strongly nonequilibrium plasma. This local concentration may occur either in space or time."

So, it is like POPS, but the symmetry is different.

Honestly, I think it should behave a lot like beam on beam fusion with the big difference that non-fusion collisions, even at steep angles, keep ions on a desirable trajectory. It's something like the MIGMA but with a thermal distribution. Todd Rider(Fundamental limitations on plasma fusion systems not in thermodynamic equilibrium) should have nothing to complain about.

Indeed my biggest worry is that, though it appears from my thought experiments and simulations that it MIGHT work, when I did the numerical calculations to determine energy output, I was sorely disappointed. My "giant" reactor in an MRI machine might put out 100 Watts of fusion power, though I did find that this number could be tweaked greatly by the precision of the timing of the ions entering the focus. Synchronization is easier when the device is smaller, so a smaller device might actually make more energy, and "there's plenty of room at the bottom".

Re: Fusor without inner grid?

Posted: Thu Dec 14, 2017 3:42 pm
by Richard Hull
Once again, we await the spending and loss of treasure and hope that always accompanies "its gotta' work" ideas related to the fusion quest.

ITER is certainly the biggest throw away in fusion science yet funded. The Fenley idea is but a tiny expenditure. I say let that tiny amount of money flow provided, when it fails, the people living off the initial funding don't say, "if we just could have enough to make it 50 times larger, we know she would kick in and go like a bandit."

How big and costly does something have to be before we get that first kilowatt of usable electricity that is over unity?

Richard Hull

Re: Fusor without inner grid?

Posted: Mon Feb 25, 2019 10:55 am
by Patrick Lindecker
Hello John,

With some delay..., I read, with great interest, your patent. I noted that more or less the principle is the same as the SEM-fusor:
* radial electromagnetic confinement,
* axial electrostatic confinement.
However, the trick is, rather to inject ions (as with the SEM-fusor) to ionize molecules with an energetic beam, so that the created ions are going to rotate, all passing (theoritically) regularly at their birth point (so along the beam axis), the Larmor radius depending on the initial radial speed, this to increase the probability of collision (fusion or not). As this radial speed is, a priori, slow, this Larmor radius with be very short (let's say less than one cm).

However as it is aimed to electricity production, I have several questions, as I'm not sure to understand all.

To get fusion interaction, particles need kinetic energy (ideally 80 KeV for D-T fuel and more for others fuels). Is this one given by the two electrodes, supposed at a big positive voltage (not indicated on the patent), the axial periodic movement of the ions being the source of kinetic energy?

What about:
* the elastic collisions with neutrals, which are going to rapidly absorb the ions kinetic energy,
* the coulombian collisions which are going to thermalize the ions energy,
* the space charge which is going to spread radially the ions?
This because the very most probable are non-fusion collisions and also because the cyclotronic rotation period of the ions is going to rapidly change due to these interactions.

About the fusions production and yield, I have a doubt because the ions density will be weak and so will be the fusion production, this with a yield surely close to the standard (i.e about 1E-6 to 1E-9).
Note I suppose that you are not in the case of a full plasma (i.e no neutrals as on tokamaks), but with only a very small percentage of ions in the plasma.
Have you tested or simulated (with a particles simulation) your idea?

Regards
Patrick Lindecker

Re: Fusor without inner grid?

Posted: Fri May 31, 2019 5:41 pm
by John Fenley
Thank you for taking a look at my device, you seem to understand the idea very well.

First, I'm only focusing on a prototype for now to prove the design. The MRI machine I intend to use has a field strength of .35T, and uses permanent magnets.

Though the initial energy of ionization will provide only a very small orbit, my hope is that repeated pulses will add energy to the ions. As the energy increases, over 15kev the radius will grow to around 10cm. 40cm(allowing a diameter on each side of the focus) is well within the uniform field volume of the MRI machine.

For now, the overall ion density will be very low, and appear more like beam on beam fusion during collisions.

The hope is to start with very low density and convert all neutrals into orbiting ions. Collisions will be most likely at the focus. The energy distribution will be thermal, and random in direction, but sychronised. With very low density, I will ignore the space charge for now, as well as any self generated magnetic fields as they should not be significant.

I have done a couple of simulations that show regular motion, and instability at high density, but I was limited by the capabilities of the software I used.

https://youtu.be/NnbfgTP7v5M

https://youtu.be/RT6nvmN7GB0

The hope is that the long total confinement times possible in a penning trap, can be combined with high energies required for fusion, while avoiding ion drift by localizing the collision volume to the diameter of the electron beam... a beam which can be made extremely narrow.

Re: Fusor without inner grid?

Posted: Sat Jun 01, 2019 5:33 pm
by Patrick Lindecker
Hello John,

Thanks for the information.

I agree that the diamagnetic field can be neglected, but the space charge is fondamental if your plasma is not neutral and I think it's the goal here to dissociate D2 molecules in ions.

The space charge is an expanding pressure which is in equilibrium with the radial electrostatic and, mainly, the magnetic pressure (the electrostatic one being much weaker than the magnetic one).

If the density is very low (as in a Penning trap), the space charge and the fusion energy will be very low also, but the confinement will be very good. If the density is high, the space charge will be high also, coullombian collisions between ions will be numerous, the orbits will not be circular nor regular and you will lose ions. Moreover, the focus will be broad.

Note: in your diagram the solenoids must normally be at a distance L <= to the radius R to have a quasi-homogenous field. If L/R>1 (as displayed), you have a system of magnetic mirrors, with a radial magnetic field component and the axial B field not homogeneous at all.

I hope you will success.

Patrick Lindecker

Re: Fusor without inner grid?

Posted: Tue Jun 11, 2019 3:44 am
by John Fenley
The rings in the patent diagram are the positive electrodes that provide end containment (probably about +60kv). The magnetic field is uniform, and externally generated by placing the chamber in an MRI machine. The field in an MRI machine is about as homogeneous a magnetic field as humans have ever made.

There is a worry that high space charges can disrupt the coordinated motion resulting in a loss of focus or timing. It is currently the biggest unknown with this design.

I have a couple of ideas, but until I can better simulate it, or build one, there is really no way to know if it will be a problem or not, and if so, at what ion densities.