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Point out news stories, on the net or in mainstream media, related to polywell fusion.

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

Post by D Tibbets »

happyjack27 wrote:
mvanwink5 wrote:You could synchronize firing a laser to ionize the pellet at the right place. Just a thought.
sounds like an excellent idea to me. i would think "the right place" would be at the point inside the wiffleball boundary where the ions will have just enough momentum to be reflect just at the edge of the electrostatic well, with a safe margin. sort of like shuffle-ball.
Change laser to Maser (microwaves) and you are describing efforts already tried, or at least contemplated. Microwaves can magnify the ionization rates.
Using the Z- pinch example. I could see dropping a pellet into the machine and then zapping it to vaporize it. The question then becomes how much of the produced gas is ionized by the by the zapping. If a significant portion remained neutral gas, it would probably have higher velocities than a puff of cold gas, and the edge ionization would suffer. Alternatly, if the zapping created a cloud of hot ions, that would defeat the purpose of havig low energy ions at the Wiffleball edge.

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

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

Post by D Tibbets »

Skipjack wrote:
With capacitors. Thy may have had sufficient power (~1.5 to 2.5 MW)but only till the capacitors drained- end of test.
I thought they were all pulsed until now anyway?
Pulsing is relative. Bussard was happy to get ~ 0.25 seconds of operation as that was enough to prove most of the physics. But it left some questions. Longer 'pulses' would have given better information about ion thermalization times, and possibly other issues. Pulses of ~ 10-100 ms (with appropriate diagnostics- another problem WB 6 had) would have disarmed critics on issues of thermalization, confluence(?), etc. The neutron signal would be less noisy, x- ray measurements would be easier, and thus possibly addressed some of the Bremsstrulung issues, etc, etc.
Steady state (like minutes to years ) are necessary more for engineering issues and production issues, not physics issues.. This is in contrast to DPF which is definitely a pulsed machine. The Polywell is definitely a steady state machine, just the definition of the steady state period that is possible or needed is in question. Steady state conditions may be obtained and maintained for only 20 milliseconds and be repeated 100 times a second in a production plant. Whether you call this a pulsed machine or a steady state machine is a matter of semantics. Even stars could be considered as steady state of pulsed (especially pulsating of flare stars, repeating nova, etc.) machines, depending on how you set up your definitions. You could even apply pulsation behavior around a steady state mean. POPS may fit into this definition.

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

Skipjack
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Joined: Sun Sep 28, 2008 2:29 pm

Post by Skipjack »

Dan, you are of course right...

happyjack27
Posts: 1439
Joined: Wed Jul 14, 2010 5:27 pm

Post by happyjack27 »

D Tibbets wrote:
happyjack27 wrote:
mvanwink5 wrote:You could synchronize firing a laser to ionize the pellet at the right place. Just a thought.
sounds like an excellent idea to me. i would think "the right place" would be at the point inside the wiffleball boundary where the ions will have just enough momentum to be reflect just at the edge of the electrostatic well, with a safe margin. sort of like shuffle-ball.
Change laser to Maser (microwaves) and you are describing efforts already tried, or at least contemplated. Microwaves can magnify the ionization rates.
Using the Z- pinch example. I could see dropping a pellet into the machine and then zapping it to vaporize it. The question then becomes how much of the produced gas is ionized by the by the zapping. If a significant portion remained neutral gas, it would probably have higher velocities than a puff of cold gas, and the edge ionization would suffer. Alternatly, if the zapping created a cloud of hot ions, that would defeat the purpose of havig low energy ions at the Wiffleball edge.

Dan Tibbets
you dont have to zap it at the wb edge. you can zap it anywhere inside the wb you need to to make the ion energies turn out right. the electrons will just scatter and diffuse inside the wb in a nanosecond. their mass is almost 4 orders of magnitude less so their inertia is negligible and their magnetic field interaction is totally dominant.

jabowery
Posts: 63
Joined: Sun Jun 29, 2008 8:52 am

Post by jabowery »

Northstar wrote: So they're needing a megawatt of input power on the electron guns alone, not mentioning the ion guns.

Does THAT number tell anyone anything about how well things are working?
No. What is the duration of that power?

ladajo
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Joined: Thu Sep 17, 2009 11:18 pm
Location: North East Coast

Post by ladajo »

As I am asleep at the wheel, I did not catch this until now...
Date Signed (mm/dd/yyyy) : 12/20/2011
Effective Date (mm/dd/yyyy) : 12/20/2011
Completion Date (mm/dd/yyyy) : 09/30/2012
Est. Ultimate Completion Date (mm/dd/yyyy) : 03/31/2014
Supplemental Agreement for work within scope
Plasma Wiffleball 8.0
https://www.fpds.gov/common/jsp/LaunchW ... ersion=1.4

But of note, is that the money did not change (on this), just the target dates.
The development of atomic power, though it could confer unimaginable blessings on mankind, is something that is dreaded by the owners of coal mines and oil wells. (Hazlitt)
What I want to do is to look up C. . . . I call him the Forgotten Man. (Sumner)

Ivy Matt
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Joined: Sat May 01, 2010 6:43 am

Post by Ivy Matt »

Any idea what it means? I'm guessing it means testing on WB 8.0 is currently scheduled to be concluded by September 30th of this year, with optional testing of WB 8.1 to be completed by March 31st, 2014. I don't see any more advanced device being approved without additional funding.
Temperature, density, confinement time: pick any two.

TallDave
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Joined: Wed Jul 25, 2007 7:12 pm
Contact:

Post by TallDave »

IIRC WB-6 had around 1MW input as well. I remember looking at this when we were trying to figure out what favorable loss scaling would look like in WB-8. It's important to remember how losses (inputs) are supposed to scale -- at B^.25 * r ^2, the input to even a 1.5M reactor is only an order of magnitude or so more than WB-6/7, the confinement and power density (output) just gets way, way better.

It sounds like they saw more maxwellianization than expected, since they're talking about well depths (and of course there was always some doubt about the claimed annealing). I would characterize this as "meh" -- mildly disappointing. The Polywell probably lives or dies on the high-beta confinement question, as Rick's ITER comparison tended to argue.
n*kBolt*Te = B**2/(2*mu0) and B^.25 loss scaling? Or not so much? Hopefully we'll know soon...

mvanwink5
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Location: N.C. Mountains

Post by mvanwink5 »

TallDave wrote:It sounds like they saw more maxwellianization than expected, since they're talking about well depths (and of course there was always some doubt about the claimed annealing). I would characterize this as "meh" -- mildly disappointing. The Polywell probably lives or dies on the high-beta confinement question, as Rick's ITER comparison tended to argue.
Did I miss something? What implied this? Thanks
Best regards
Counting the days to commercial fusion. It is not that long now.

Roger
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Joined: Fri Jul 06, 2007 2:03 am
Location: Metro NY

Post by Roger »

mvanwink5 wrote:Did I miss something? What implied this? Thanks
Best regards
2nd the motion, I value Daves input.
I like the p-B11 resonance peak at 50 KV acceleration. In2 years we'll know.

ladajo
Posts: 6258
Joined: Thu Sep 17, 2009 11:18 pm
Location: North East Coast

Post by ladajo »

(and of course there was always some doubt about the claimed annealing).
The IAC paper would seem to take it past claimed, and make it an observed. (from page 7)
Ions spend less than 1/1000 of their lifetime in the dense, high energy but low cross-section core region, and the ratio of Coulomb energy exchange cross-section to fusion cross section is much less than this, thus thermalization (Maxwellianization) can not occur during a single pass of ions through the core. While some up- and down- scattering does occur in such a single pass, this is so small that edge region collisionality (where the ions are dense and “cold“) anneals this out at each pass through the system, thus avoiding buildup of energy spreading in the ion population (Ref. 14).

[14]. Bussard R.W. and King K.E., “Bremmstrahlung and Synchrotron Radiation Losses in Polywell™ Systems“, EMC2 Technical Report 1291-02, December 1991.
http://www.askmar.com/ConferenceNotes/2 ... 0Paper.pdf
The development of atomic power, though it could confer unimaginable blessings on mankind, is something that is dreaded by the owners of coal mines and oil wells. (Hazlitt)
What I want to do is to look up C. . . . I call him the Forgotten Man. (Sumner)

Roger
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Joined: Fri Jul 06, 2007 2:03 am
Location: Metro NY

Post by Roger »

Thanks Ladajo, SO if EMC2 is building- installing new E-guns, because of an anomoly, maybe thermalization isnt at a problematic level?

Is it possible the old E-gun placement effected a process in the outter regions? Annealing?

If so is the solution, slightly stronger e-guns and placement slightly withdrawn?

I'm probably grasping at straws, if so forgive me. The news of the E-gun work has been tweaking my curiousness something fierce.
I like the p-B11 resonance peak at 50 KV acceleration. In2 years we'll know.

polywellfan
Posts: 33
Joined: Thu Apr 12, 2012 3:05 pm

Post by polywellfan »

ladajo wrote:
https://www.fpds.gov/common/jsp/LaunchW ... ersion=1.4

But of note, is that the money did not change (on this), just the target dates.
The link doesn't work for me and I didn't found an entry for EMC2 on myself, except for this: https://www.fpds.gov/common/jsp/LaunchW ... ersion=1.4 and it does not fit:


Award ID (Mod#):

N0010410MQ722 ( 0 ) (View) Award Type: Purchase Order
Vendor Name: EMC2, INC. Contracting Agency: DEPT OF THE NAVY
Date Signed: July 01, 2010 Action Obligation: $96,479.51
Referenced IDV: Contracting Office: NAVSUP WEAPON SYSTEMS SUPPORT MECH
NAICS (Code): COMPUTER AND SOFTWARE STORES ( 443120 ) PSC (Code): ADP SUPPORT EQUIPMENT ( 7035 )
Vendor City: STERLING HEIGHTS Vendor DUNS: 083941799
Vendor State: MI Vendor ZIP: 483142119

ladajo
Posts: 6258
Joined: Thu Sep 17, 2009 11:18 pm
Location: North East Coast

Post by ladajo »

Wrong EMC.
Try search by "energy/matter"

or you can use the DUNS number.
The development of atomic power, though it could confer unimaginable blessings on mankind, is something that is dreaded by the owners of coal mines and oil wells. (Hazlitt)
What I want to do is to look up C. . . . I call him the Forgotten Man. (Sumner)

ladajo
Posts: 6258
Joined: Thu Sep 17, 2009 11:18 pm
Location: North East Coast

Post by ladajo »

A little birdy told me last week the new contract mod should be signed by the end of the month.

Thought you all might want to know.

I do find it encouraging that ONR has not only continued the project, but furthered the funding.

That said, it is not certain it will succeed as a viable device. But, we shall see. Good science.
The development of atomic power, though it could confer unimaginable blessings on mankind, is something that is dreaded by the owners of coal mines and oil wells. (Hazlitt)
What I want to do is to look up C. . . . I call him the Forgotten Man. (Sumner)

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