Flux Compression Generator

[Mark Rowley]

I have been doing a bit of research on this device lately. Based upon the input/output power ratios, it seems that this thing is many times over-unity.

Other than its current(non-scientific) use, has any research been done in using this to "supercharge" a Tokamak ? It seems that this very simple device could have promise in alternative power generation.

Mark Rowley

[Richard Hester]

It's not over unity at all - the process uses a few kilos of explosive to compress a magnetic field entrained by a solenoid or such. The explosive provides the energy. The tokamak brotherhood have enough problems with their expensive, tempramental beasts without having to blow them up to get results...

[Adam Szendrey]

The FCG i'm familiar with , is destroyed in the process of generating the high energy pulse. They are very useful in EMP weapons, but how would you build a useful power generator based on it? Maybe by using a plasma to achieve the same propagating short circuit along the coil?
Now that i read Richard's reply i agree with him. I also thought that the explosive provides the energy.

Btw, it would be really funny to see those "scientist" blow the lab up, and then run out, all dirty, yelling "we got it!", lol.

Adam

[Mark Rowley]

An old article in Popular Mechanics discusses this device and provides some yield data. See the below listed link.

The article states: "The result is that FCGs will produce a ramping current pulse, which breaks before the final disintegration of the device. Published results suggest ramp times of tens of hundreds of microseconds and peak currents of tens of millions of amps." The pulse that emerges makes a lightning bolt seem like a flashbulb by comparison.

Based upon that, a system could be devised to channel the current into the Tokamak( or Larrys pulsed fusor) from the remote detonation location. A large buss bar system is all that is needed.

Imagine if a large FCG was built using the conventional power of a Daisycutter or MOAB. It may just be enough to ignite the fusion torch.

Here is the link:
http://www.popularmechanics.com/science ... dex2.phtml

Mark Rowley

[Adam Szendrey]

I think , that such a powerfull current pulse, directed into such a small device as a fusor, would desintegrate the whole setup. I may be wrong ofcourse. But i doubt that such explosives are cheap, or economical, and think of the expenses to constantly replace the destroyed solenoid.
As an experiment it would be quite expensive, and as a way of generating electrical power i think it's a dead end.

Adam

[Mark Rowley]

Hey, for info I was JOKING about the fusor. That is why this message was posted in th Other Forms of Fusion section.

I will disagree with you about the fact that this is a 'dead-end' for a possible power system. You are too quick to say "no". Think about it, everyone said no about the fusor decades ago. Why are we here then ? To further research on a stated 'dead-end' issue. I dont propose building a device like this, however for the yield that it produces, it could be useful in research.

BTW, compared to the gigantic capacitive discharge system used here at Lawrence, the explosives and subsequent solenoid would compare at pennies on the dollar. Explosives are cheap when it comes to government spending.

Mark Rowley

[Richard Hester]

The problem is, every time you fire the setup, you will need to start all over again. I wouldn't think of touching the explosives part of it myself, especially given the current political climate.

[Brian McDermott]

From my experience in amateur rocketry, I can tell you that obtaining explosives legally is not a trivial matter. The ATF explosives permitting process is comparable to the NRC Tritium permitting process, albeit a bit tamer and within reach of the dedicated amateur.

You waive your 4th amendment rights and are open to unwarranted and unannounced searches at any time of day. You need to have a special, super heavy duty storage magazine located 200' from any road or building, built to special regulations (can you say locks with 5/8 inch shackles?). You need to keep meticulous records and inventories of all your explosive materials. You'll also need to obtain state and local permission. After those requirements are met, you can apply for the $200 permit, including fingerprinting, background checks and body cavity search.

After that, feel free to get all the explosives you want, as they are not really that expensive.

(note: This requirement is for buying explosives only. The ATF ironically does not require permits for explosives manufactured for personal use. That is why adavnced amateur rocketeers can get around the regulations. But who really wants to make high explosives in the garage?)

[Richard Hester]

The type of high velocity explosives one would really want to use for field compression experiments probably aren't that easy to get even after the permit requirements are satisfied, as they would fall under the catagory of military ordinance. Thanks - I want to keep all my appendages.....

[Mark Rowley]

I guess I should break this down into basics. I would not propose this as an amateur project unless someone can devise an FCG that dosent use explosives. It was just a curiosity as to why government labs such as Livermore(my neighbor) hasnt pursued this angle. It is an "Ignition" facility after all. They sure enough have the acreage to detonate almost anything without bothering the neighborhood.

Mark Rowley

[Adam Szendrey]

Mark, i agree, that every possible route should be pursued. But to me this just doesn't feel like a possible way. A power plant that constantly blows something up (ofcourse if only a single blast is needed at start, that's better somewhat). The price of the super fast explosive and the amount that is needed...plus energy is required to produce that explosive, to manufacture the coils, etc. All of the above is more of a problem if a constant pulsing is required.
But if i understand correctly, what you want is to "ignite" self-sustaining fusion, and then only something that confines it is needed.

BUT (and this made me thinking),maybe the FCG can be downscaled a bit, and converted, so no explosive is needed.

What i mean is for example a plasma (i i'm not mistaken a plasma is a pretty good conductor) traveling down along the axis of the coil periodically , in proper sync with the current state of the coil. This way a rapid pulsing may be possible.

Though i'm affraid any material coming in contact with a plasma will evaporate. But maybe if the plasma is thin and fast enough...ideas?

Adam

[Frank Sanns]

There is only a total amount of energy in a magnetic field around a coil. I do not see the difference between a traveling collapse and a short put simultaeously along the lenght of the coil. Sure there would be harmonics and a frequency spread but there would be no more energy.

Frank S

[DaveC]

It seems to me we may be confusing "power" and "energy" here. Tens of milions of amps, is not either power or energy per se. One needs to have a potential along with the charge.

Whatever the potential is, the duration of the entire event spells out how much energy is delivered. When you add the energy of the magnetic field.. (1/2 L*I^2) and the energy of the explosion, you have all the energy of the system. As to whether this enormous current would improve the neutron yield in a pulsed fusor (assuming such a device could in fact be built) , Given that we are presently about 14 orders of magnitude below breakeven at the 1 watt level, it is asking a lot to expect greater than breakeven in the mega or giga-watt levels. That would imply a 23 order of magnitude improvement in fusion probability.

Seems a bit unlikely at this stage.

Dave Cooper

[Mark Rowley]

There have been many posts in the past which elude to a "barrier" that may need to be passed before the efficiency becomes acceptable. This barrier is also mentioned in the Perfessors book.

If its true, and there is in fact an envelope that needs pushing, then maybe we should be concentrating on theoretical ways of igniting this torch. I am not sure if the current preoccupation of neutron count is really the proper direction. I am worried that this whole thing may be turned into a numbers contest as opposed to some real direction. We all have alot of fun working on this project, but I believe its one with a future. I also believe this is what draws most of us here.

Just my thoughts for the day.

Mark Rowley

[Starfire]

Meterology is important Mark, it is the path of understanding and quantifying the events observed. It provides a basis for analysis and record, from which comparisions can be made and meaningful direction taken. The board is diverse in servicing many disciplines and there are no constraints imposed in the various directions which each worker must pursue or explore. I for one, learn much from this diversity and value the in-depth and detailed work down by others. By this precession they become masters and experts. All are free to pursue there own direction and to specialise as they choose. All diversion is contribution and many blind alley's will be ventured down with great enthusiasm.

[Mark Rowley]

Very well stated. Everyone here is free to do whatever they want. All I am saying is that reducing this to a numbers game seems odd. I doubt that was the direction of the Farnsworth team or ITT. The Fusor to me seems promising and requires further research(as we all seem to agree upon). I suppose I part ways when I say it will require some radical changes in Fusor design(or testing) to achieve some better results. I guess that is why I like Larrys Pulsed fusor work. Its a radical design that shows true innovative spirit.

Mark Rowley
Fusion Optimist

[Starfire]

I actually agree Mark It is just that to achieve the standard mark set by Richard, Jon etc. is the first goal for many - after that - who knows. But as Larry say's Fusion is Fun.

[fastimports3]

There is a FCG that is not a bomb that will generate terrawatts of current. It's used to power military high energy weapons and is said to be classified. Here's the info I have to share on it.

MAGNETIC PULSE COMPRESSION (MPC)
Magnetic pulse compression utilizes reactors in conjunction with capacitors to shape input pulses into narrow output pulses of much higher current . MPC, therefore, allows the designer to use less expensive input switches with lower current ratings. MPC can also extend the lifetime of the input switch. Advanced MPC devices - capable of generating power levels of multi-terawatts in tens of nanoseconds - have been realized utilizing Metglas® cores.

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+ Research
* INDUCTION ACCELERATORS
o Drivers for Free Electron Laser
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o High Power microwave sources (relativistic Klystrons)
o Heavy ion accelerators for inertial confinement fusion research

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Metglas®, Inc. requests that the applications and approval accompany any request for samples, quotations, or purchase orders.

[Carl Willis]

>terrawatts of current

Current does not have dimensions of watts (or "terrawatts," whatever those are).

With all due respect, this thread is seven years old and there is absolutely no reason to resurrect it now with a bunch of scientifically-illiterate mumbo-jumbo. The discussion is closed.

-Carl