Lockheed Martin news

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

Moderators: tonybarry, MSimon

happyjack27
Posts: 1431
Joined: Wed Jul 14, 2010 5:27 pm

Re: Lockheed Martin news

Postby happyjack27 » Thu Dec 15, 2016 12:55 am

I erred when I said "constant force". The force is the arithmetic difference in voltage per distance. Whereas the voltage drops off geometrically. Nonetheless, it would still "oscillate/orbit" since all you need for that is a central force dependant only on absolute distance from the center.

The recirculation will certainly interferes with the beam, quite possibly a lot given the number of recirculations. However, the forces, at least, are additive. So an improved focused is still an improved focus, regardless of intervening factors.

I don't suspect much difference between face vs corner, except that faces would be more stable, as a single spin about the axis on a corner exposes you to more extreme forces.

I'm reminded of "Shannon entropy" being maximized when the probability distribution is "flat". I suspect the same applies here (except minimized) - a circular cusp of a given radius provides less destabilization than a square one with the same average radius, all else being equal.

happyjack27
Posts: 1431
Joined: Wed Jul 14, 2010 5:27 pm

Re: Lockheed Martin news

Postby happyjack27 » Thu Dec 15, 2016 1:16 am

This is all premises on the idea that - in terms of KE, at least - you can collimate ions better than electrons.

If this is false, it might not be worth it

D Tibbets
Posts: 2774
Joined: Thu Jun 26, 2008 6:52 am

Re: Lockheed Martin news

Postby D Tibbets » Thu Dec 15, 2016 2:13 am

happyjack27 wrote:This is all premises on the idea that - in terms of KE, at least - you can collimate ions better than electrons.

If this is false, it might not be worth it


I would expect this to be the case. The focus may not be better, but the subsequentspread of the collimated ions in the beam would spread more slowly due to their greater momentum/ inertia. The electrons spread faster at the same energy. The ions may impede this some as a charge separation builds. But the electrons in a group create a space charge that can forcefully accelerate ions much more than individual coulomb collisions would- that is the whole idea of using a potential well.

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

happyjack27
Posts: 1431
Joined: Wed Jul 14, 2010 5:27 pm

Re: Lockheed Martin news

Postby happyjack27 » Thu Dec 15, 2016 2:24 am

D Tibbets wrote:
happyjack27 wrote:This is all premises on the idea that - in terms of KE, at least - you can collimate ions better than electrons.

If this is false, it might not be worth it


I would expect this to be the case. The focus may not be better, but the subsequentspread of the collimated ions in the beam would spread more slowly due to their greater momentum/ inertia. The electrons spread faster at the same energy. The ions may impede this some as a charge separation builds. But the electrons in a group create a space charge that can forcefully accelerate ions much more than individual coulomb collisions would- that is the whole idea of using a potential well.

Dan Tibbets



If I understand right, you're saying that, while the KE energy exchange is the same both ways, one also must consider time. The ions, accelerating slower, will spend more time in a given electron relation - their electric field will changes a lot slower.

But electrons filling in that gap... All things considered I think a simulations is in order.

Ions surrounded by a ring of electrons vs vice-versa.

At the same KE vs the same velocity.

At whatever one is in the center at a given KE vs it at a given velocity.

So 2x2x2 = 8 simulations.

edit: 12. Also having both streams in the center, because why not?
Last edited by happyjack27 on Thu Dec 15, 2016 2:30 am, edited 3 times in total.

mvanwink5
Posts: 1762
Joined: Wed Jul 01, 2009 5:07 am
Location: N.C. Mountains

Re: Lockheed Martin news

Postby mvanwink5 » Thu Dec 15, 2016 2:25 am

I don't know how high energy neutral beams are being made, but clearly, the method has been proven and Tri Alpha is planning to pump in megawatts of power into their plasma in C2U with these beams. Why reinvent the wheel? Why debate it? Find out how it is being done is my suggestion.
Near term, cheap, dark horse fusion hits the air waves, GF - TED, LM - Announcement. The race is on.

happyjack27
Posts: 1431
Joined: Wed Jul 14, 2010 5:27 pm

Re: Lockheed Martin news

Postby happyjack27 » Thu Dec 15, 2016 2:43 am

mvanwink5 wrote:I don't know how high energy neutral beams are being made, but clearly, the method has been proven and Tri Alpha is planning to pump in megawatts of power into their plasma in C2U with these beams. Why reinvent the wheel? Why debate it? Find out how it is being done is my suggestion.


You can't always get an accurate sense of how well a project is doing from their quarterly investor relations reports.

Having said that, why not both?

An important part of science is verification.

And it certainly would not subtract from one's knowledge or idea base to know how the thing works.

D Tibbets
Posts: 2774
Joined: Thu Jun 26, 2008 6:52 am

Re: Lockheed Martin news

Postby D Tibbets » Sat Dec 17, 2016 1:17 am

happyjack27 wrote:
D Tibbets wrote:
happyjack27 wrote:This is all premises on the idea that - in terms of KE, at least - you can collimate ions better than electrons.

If this is false, it might not be worth it


I would expect this to be the case. The focus may not be better, but the subsequentspread of the collimated ions in the beam would spread more slowly due to their greater momentum/ inertia. The electrons spread faster at the same energy. The ions may impede this some as a charge separation builds. But the electrons in a group create a space charge that can forcefully accelerate ions much more than individual coulomb collisions would- that is the whole idea of using a potential well.

Dan Tibbets



If I understand right, you're saying that, while the KE energy exchange is the same both ways, one also must consider time. The ions, accelerating slower, will spend more time in a given electron relation - their electric field will changes a lot slower.

But electrons filling in that gap... All things considered I think a simulations is in order.

Ions surrounded by a ring of electrons vs vice-versa.

At the same KE vs the same velocity.

At whatever one is in the center at a given KE vs it at a given velocity.



So 2x2x2 = 8 simulations.

edit: 12. Also having both streams in the center, because why not?



I'm getting further and further out of my depth here. Obviously neutral beam methods are complex, involved and the basis of much research, pHD work, post doc work, industrial and government work. Things like debye length, debye shielding, plasma frequency , etc apply and my understanding is minimal and irrelevent. Except, I will mention Dr Bussard's lament that younger physicists are not trained in the vacuum tube technology of his generation.

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

happyjack27
Posts: 1431
Joined: Wed Jul 14, 2010 5:27 pm

Re: Lockheed Martin news

Postby happyjack27 » Sat Dec 17, 2016 2:09 am

D Tibbets wrote:
happyjack27 wrote:
D Tibbets wrote:
I would expect this to be the case. The focus may not be better, but the subsequentspread of the collimated ions in the beam would spread more slowly due to their greater momentum/ inertia. The electrons spread faster at the same energy. The ions may impede this some as a charge separation builds. But the electrons in a group create a space charge that can forcefully accelerate ions much more than individual coulomb collisions would- that is the whole idea of using a potential well.

Dan Tibbets



If I understand right, you're saying that, while the KE energy exchange is the same both ways, one also must consider time. The ions, accelerating slower, will spend more time in a given electron relation - their electric field will changes a lot slower.

But electrons filling in that gap... All things considered I think a simulations is in order.

Ions surrounded by a ring of electrons vs vice-versa.

At the same KE vs the same velocity.

At whatever one is in the center at a given KE vs it at a given velocity.



So 2x2x2 = 8 simulations.

edit: 12. Also having both streams in the center, because why not?



I'm getting further and further out of my depth here. Obviously neutral beam methods are complex, involved and the basis of much research, pHD work, post doc work, industrial and government work. Things like debye length, debye shielding, plasma frequency , etc apply and my understanding is minimal and irrelevent. Except, I will mention Dr Bussard's lament that younger physicists are not trained in the vacuum tube technology of his generation.

Dan Tibbets



I recall that. My impression was that th younger generation is more schooled on solid state physics as opposed to plasma physics.

A brute force time and space simulation is going to suffer from "rounding errors", for lack of a better word, at high frequencies (both spatial and temporal.) Not to mention low particle count.

Though I don't imagine any of these limitations would be prohibitive just shooting two co-linear particle steam towards a solenoid. There are neither high frequencies involved, nor Debye sheaths.

Skipjack
Posts: 5881
Joined: Sun Sep 28, 2008 2:29 pm

Re: Lockheed Martin news

Postby Skipjack » Wed Mar 15, 2017 5:54 am

I have not seen this posted yet, but might have simply missed it. It is an analysis of the Lockheed Martin reactor concept. I am honestly a bit at a loss:
https://github.com/ThePolywellGuy/Posts-On-PDF/blob/master/41%20-%20An%20Intensive%20Analysis%20of%20Lockheed%20Fusion%20Research%20(12-11-2016).pdf

NotAPhysicist
Posts: 72
Joined: Wed Jul 15, 2015 9:51 am

Re: Lockheed Martin news

Postby NotAPhysicist » Wed Mar 15, 2017 12:36 pm

That's a great find, thank you :)
Certainly sounds positive at Lockheed and would also seem to highlight how unfortunate it is that the Polywell concept hasn't been better funded.
Getting there I suppose.

crowberry
Posts: 411
Joined: Sun Sep 08, 2013 6:34 am

Re: Lockheed Martin news

Postby crowberry » Wed Mar 15, 2017 3:34 pm

Skipjack wrote:I have not seen this posted yet, but might have simply missed it. It is an analysis of the Lockheed Martin reactor concept. I am honestly a bit at a loss:
https://github.com/ThePolywellGuy/Posts-On-PDF/blob/master/41%20-%20An%20Intensive%20Analysis%20of%20Lockheed%20Fusion%20Research%20(12-11-2016).pdf


Mattman posted this multiple times in different forums back in December last year, but not in this thread for some reason:
http://www.talk-polywell.org/bb/viewtopic.php?f=2&t=6267
http://www.talk-polywell.org/bb/viewtopic.php?f=3&t=6268
http://www.talk-polywell.org/bb/viewtopic.php?f=4&t=6269
http://www.talk-polywell.org/bb/viewtopic.php?f=5&t=6270

Skipjack
Posts: 5881
Joined: Sun Sep 28, 2008 2:29 pm

Re: Lockheed Martin news

Postby Skipjack » Wed Mar 15, 2017 6:58 pm

Oh Ok, I don't look into those forums as often.

hanelyp
Posts: 2198
Joined: Fri Oct 26, 2007 8:50 pm

Re: Lockheed Martin news

Postby hanelyp » Wed Mar 15, 2017 7:03 pm

Re: https://github.com/ThePolywellGuy/Posts-On-PDF/blob/master/41%20-%20An%20Intensive%20Analysis%20of%20Lockheed%20Fusion%20Research%20(12-11-2016).pdf
Last May, they
set a record for the longest stable Field Reversed Configuration, at five microseconds [21]. This
might not sound momentous, but critically, their machine was fusing for the duration of the
run. This implies that if TAEs’ machine can run for two hours, then they can get two hours of
continuous fusion.

No, merely implies that any relevant instability takes more than 5uS to become critical.

Re: dipole shielded stalks:
Works fantastic in 2D. In 3D it gets messy enough as the stalk approaches the main coil that I'm not sure how well it works.
The daylight is uncomfortably bright for eyes so long in the dark.

Skipjack
Posts: 5881
Joined: Sun Sep 28, 2008 2:29 pm

Re: Lockheed Martin news

Postby Skipjack » Wed Mar 15, 2017 7:31 pm

hanelyp wrote:Re: https://github.com/ThePolywellGuy/Posts-On-PDF/blob/master/41%20-%20An%20Intensive%20Analysis%20of%20Lockheed%20Fusion%20Research%20(12-11-2016).pdf
Last May, they
set a record for the longest stable Field Reversed Configuration, at five microseconds [21]. This
might not sound momentous, but critically, their machine was fusing for the duration of the
run. This implies that if TAEs’ machine can run for two hours, then they can get two hours of
continuous fusion.

No, merely implies that any relevant instability takes more than 5uS to become critical.

Re: dipole shielded stalks:
Works fantastic in 2D. In 3D it gets messy enough as the stalk approaches the main coil that I'm not sure how well it works.

TAEs record was 5 milliseconds, not microseconds (that's a factor of 1000 more) and they have since then managed to get up to 12, when their power supply ran out.
The curve was a completely flat horizontal line until the end. It looks like they can indeed hold it forever, at least at that temperature. They are now going to test whether they can keep it stable with higher temperatures with their next device.

Also worth mentioning is that Sam Cohen's (PPPL) RMF stabilized FRC has had 300 ms pulse lengths...

D Tibbets
Posts: 2774
Joined: Thu Jun 26, 2008 6:52 am

Re: Lockheed Martin news

Postby D Tibbets » Thu Mar 16, 2017 12:52 am

5 milliseconds or more may be very significant, or not. For a Polywell operating at a density of 10^22 /M^3 it is impressive. But, I don't know at what density the Tri Alpha current efforts are working at. It is that old triple product consideration. Low Beta Tokamaks may manage 100s of seconds, but because of the lower density, the triple product is still a challenging goal.

I understand reverse field configurations may reach densities similar to Polywell goals, but I don't know how this relates to their current research, nor how confident they are of scaling projections for either density or temperature .9the other two legs of the triple product).

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


Return to “News”

Who is online

Users browsing this forum: No registered users and 6 guests