Talk-Polywell.org

Here is many informations on this forum, but only one thing i can't find. How much kV, A, W... are on polywell input and how much is on output?
How big eficiency is when trying to heat water inside reactor?
Polywell is open source but I can't find most important numbers so help please...

Polywell is still an experimental machine, not a working machine. No real data are available for now. Also IS NOT open source, but proprietary.

Maybe you are confusing with something else.

I don't believe EMC2 has said whether they'll release any of their results to the public.

Perhaps you're thinking of Famulus, who has built his own Polywell device, based on one built at the University of Sydney, and should be testing it soon. He intends to release his results once he has them.

Try looking in: Technical FAQ.

The first thread in this forum stated that the purpose of this forum was to as a community design an open source polywell reactor. That never really came together, but there have been some interesting Idea's posted. Of course this forum, and the theory forum have so much overlap, that it's become very arbitrary where people post.

KitemanSA wrote:Try looking in: Technical FAQ.

The link brings up an empty page for me.

Dan Tibbets

Looks like we have an a$$hole who likes to delete things.
If it happens again, click on history and undo the guy's evil.

PS: Why would anyone want to do something like that?

The only results released publically, at least for a while, was results for WB6 This information is limited to ~ 3 neutrons detected in ~ 0.25 ms when Beta presumably was ~ 1. Converted to neutrons / second (once the calibration of the neutron detectors and distance was factored in) resulted in a neutron flux of ~ 500 million neutrons /sec, which represents ~ 1 billion D-D fusions / sec. This is equivalent to ~ 1 mW (0.001 W) of fusion power.
The low voltage power for the magnets consumed perhaps ~ 20,000 W and provided 0.1 Tesla fields.
The electron current from the electron guns was ~ 40 Amps* at low voltage. The magrid had a potential of ~ 12,000 Volts, resulting in the electron power of ~ 480,000 W. So net input power was ~ 500,000 Watts.
The potential well created was at ~ 10,000 Volts, and this potential well accelerated edge created ions to ~ 10,000 eV of kinetic energy.

Density inside the machine is uncertain. Using a rough number for the Wiffleball trapping factor (1000), and the assumption that arcing-glow discharge (end of functional potential well) started at ~ 1 micron (10^-6 atmospheres) pressures outside of the Magrid, results in a density inside the Wiffleball of ~ up to ~ 10^ 22 particles /M^3. I think that the density inside this small , low B field machine was perhaps several orders of magnitude less than this. The resultant Q was ~ 2 * 10^-9. Note that A. Carlson once claimed that the Q was ~ 10^-15. This was a silly mistake on his part and was presumably based on the idea that neutrons detected equaled the neutrons produced, which is completely meaningless without the calibration factors I mentioned above.


WB 7 speculations: Initial performance may have been similar to WB6. Perhaps longer run times if the gas puffers were more percise / controllable. The run times may have been much longer in the ion gun version. Pure guess that the run times may have extended into the 10's of milliseconds. This would give significantly more information about the competing processes like annealing, thermalization, etc.
Presumably WB7 had better instrumentation, and neutron numbers to work with. Neutron counters with shorter sampling times would have been a distinct advantage over the WB6 detector which I believe had a sampling time or resolution of ~ 0.5 ms. WB 7, and WB7.1 may also have been operated over a mildly increased range of conditions- drive voltage and B field strength.
WB7.1 presumably without the nubs/ interconnects between the magnets and with ion guns may have improved output because the ions were released at an ideal distance from the center, as opposed to a more diffuse distribution of the created ions from the neutral gas puffers. And, perhaps just as important, reduced the electron input power requirements if recirculation was improved. This would be especially important for trying to utilize smaller, less powerful reactors, or advanced fuels where the maximum obtainable Q is lower.


*Quotes of the electron input power in WB6 has varied.

Dan Tibbets

There were five fusion runs on WB-6.

1) 5.0 kV, 800 A magnet current (1000 gauss) - 1 count
2) 9.8 kV, 750 A magnet current - 2 counts
3) 12.5 kV, 700 A magnet current - 2 counts
4) 12.5 kV, 800 A magnet current - 3 counts
5) 14 kV, 1000 A magnet current - 1 count, coil failure

Several tests were made prior to the fusion runs, to test wiffleball formation as well as could be managed with the available resources.

Valencia also strongly implies other WB machines produced neutrons as well, but I've never seen any data.

Here are the WB-6 input/output numbers FAQ.

http://www.ohiovr.com/polywell-faq/inde ... reactor%3F

WB-7 is very similar. There is some speculation around here about he WB-8 numbers; Rick Nebel did say the B field would be about eight times stronger than WB-6 and 7.

You seem to be asking about WB-D/100 as well, the prototype reactor. I believe the specs are 5-10MW input for 100MW output.

The FAQ is misleading. There was no 5 amp 12,000 volt power supply hooked up to the machine during the tests. Bussard had lamented that their limited power supply was not strong enough (in Amps) to power the machine to Beta=1 conditions. To circumvent this they used a capacitor bank.

The magnets were powered by marine batteries providing ~ 1000- 2000 amps at (probably) 12 volts.

The electron guns were car headlight filaments driven at 12 volts(probably*). I don't know if they had any current limiting on this circuit. But if significantly more current was drawn than the rating of the bulbs, they would have quickly burned out. The short test times may have allowed significantly greater currents, but 800 amps?

The magrid casings were charged to ~ 12,000 volts. The procedure was to use the power supply to charge the capacitors, disconnect the power supply, power up the magnets from batteries,connect the capacitors to the grid casings, turn on the low voltage electron guns, puff the gas, wait for the grid external gas to build up and short out the system, then quickly disconnect everything.

I cannot reference the WB6 report as it was withdrawn, but recollection was that the current from the electron guns was measured and plateaued at ~ 40 amps during the neutron production and presumed Beta = 1 condition. The current then shot up during the shorting phase reaching, and I think, exceeding 800 amps. But, this current was not from low voltage electron guns, but from the high voltage magrid casings to ground. Thus this current represents conditions during the failure mode of the machine due to known unavoidable limits that could not be corrected due to budget.
The significant voltage and current while the machine was reportedly performing as advertised was 12,000 V on the magrid casings accelerating ~40 Amps of 12 eV electrons from the electron guns. This results in an electron input power of ~ 480,000 Watts.

If the scaling is accurate, then the Demo 'WB100' would thus produce 100 MW of fusion power, and consume ~ 50 MW. This assumes electron containment or fusion efficiencies are not improved through better recirculation, better sphericity, etc.
If WB 6 electron input power was truly ~ 10 MW during the Beta=1 phase, then scaled up to demo conditions (R=1.5 M, B= 10 T, and at the same voltage) the fusion output would again be ~ 100 MW, but the input electron power would be ~ 1 GW. This is contrary to multiple claims, and this reinforces my point.

In a thread about WB6 power, Nebel did say that it was ~ 10 MW, but he may have been confusing the situation and he was referring to what he expected in a WB100 type machine, or referring simply what was indeed the power being consumed in WB6, but without pointing out that this was during the failure phase.

* I use the qualifier 'probably' because I'm don't know how they arranged the batteries Were they arranged purely in parallel, or also in series. I doubt more voltage was applied to the headlight filaments as that would be more stress on them, and not gain anything (the electrons might be accelerated to perhaps 12,024 eV, instead of 12,012 eV.
Higher voltage may have been used in the electromagnets, if the higher potential was needed to push the thousands of amps through the resistance of the copper wires. An electrical engineer could quickly calculate this, but I don't have any idea.

Dan Tibbets

fusion_cro wrote: How big eficiency is when trying to heat water inside reactor?

There is no thermal plant, no water.

Thermal conversion efficiency should be similar to what is achieved in coal plants of fission plants. Depending on the effort, somewhere between 25-35% efficiency is the best that can be practically achieved.

Dan Tibbets

Unless of course that supercritical CO2 Brayton cycle is perfected sometime soon.