Why 10-25 times net power?

[alexjrgreen]

What we need is an alpha receiver.

The State of the Art in Hadron Beam Cooling:
https://wiki.ornl.gov/sites/icns/HB%202 ... /Prost.ppt

[D Tibbets]

Direct conversion of charged fusion products is mentioned by Bussard (?) in this dated (~1992) review. He discusses it on page 43 and also gives a reference to a 1980's study.
The link was provided to me in another thread by KitemanSA

http://www.askmar.com/Fusion_files/EMC2 ... plants.pdf[/url]

Dan Tibbets

[chrismb]

http://www.sciencedaily.com/releases/20 ... 114433.htm

Thanks for that link, Mike, I've not see that before. I guess this was what one of the guys from Rutherford Appleton was talking about when he mentioned beam energy recovery to me recently after he saw my poster on beam fusion concepts at a poster session at Culham.

As a past Research Fellow in Computational Electro-magnetics, I have to say that clearly the process has a theoretical basis and there would be mileage in discussing it further, though I suspect the process would only really work for highly mono-energetic collimated beams as would be the case here.

But much as that discussion might be interesting, I am now disabused of the notion that this forum can maintain an objective debate of scientific merit. Particularly given the exchange above, I don't think it is a debating style I wish to participate in, nor does my participation appear to be beneficial to those on this forum who wish to debate in this style of such personalised points of reference and flamboyant presumptions of a Polywell's behaviour without any shreds of evidence or regard for the behaviour of comparable systems. So I will desist from doing so hereon.

I thought I would run through a few baseline quantitive questions first to form my own technical assessment of where the project is at.

it would be great if it turned out that you could see some potential in the project. I hope you can be convinced.

I regret to say that at this moment I am not - only, and until, clear diagnostic evidence proves otherwise. The debate on Polywell theory appears to me to be completely and fully done now and what remains is pure speculation that must be settled experimentally. The realities of trying to make this thing function as intended appears to be a lesson well learned by the EMC2 team. They appear to have settled into some down-to-earth, step-by-step and suitably restrained experimentation after all the great sales talk from Robert Bussard. His vision is in as good a set of hands as it is likely to be, but this doesn't imply likely success. Living up to the claims may prove to be a stretch too far, I fear.

By posing presumptive statements I have certainly learned much about the Polywell's intended functioning from the replies. Thank you all for that. But the waffleball theory seems to me to have more holes in (not just cusps, but also metaphorically) than I can see practical routes forward. I really don't see any reasons why the reaction volume won't thermalise out over a time-scale of realistic 'continuous' operation. Then you've got a classic magnetic confinement problem for which the Magrid's essential field structures have already been well-tried, albeit in topologically different forms but otherwise much the same. Even if the fundamentals can be demonstrated at very hard vacuum levels, I see no way past the vast sputtering vacuum contamination that is likely to occur off the Magrids if a 'real power' particle flux was to be generated.

Let me give you a hint. I know a fair amount about this stuff because I was a Reactor Operator in the US Navy.

Good for you! I have no doubt you do indeed have plenty of knowledge that I do not. During the 1990's I, albeit briefly, held the substantive rank of Lieutenant (NATO rank OF-2) in the Royal Navy as an Engineering (Training Management) Officer, though I was never commissioned to 'Fleet Strength'. Do I outrank you? [am I getting good at this 'trump' game?]

I posted that particular qualification so that you would know you weren't arguing with a pigheaded ignoramus. Not everyone can tell someone is an expert just from his posts.

What IS your background? Just so I know what I'm dealing with...

(I really hate that expression 'expert'!)

As far as affiliations go that you might recognise, I have been a member of the IEEE (EMC and Nuclear & Plasma societies) since the President of the EMC Society personally nominated me for professional membership after we met in 1999 when I was presenting a paper at ETH Zurich (hence the reference above to Einstein's alma mater). My research was on using modelling to predict sensitivity in systems and to understand when the 'theory' and a consequent electromagnetic 'model' create an unrealistic simulation of a real system. Even if the Polywell runs as advertised, my gut feeling is that it will be a fundamentally unstable system, though of course that is only a subjective opinion though it may hold some weight on this forum as this kind of background seems to permit 'rights' to make such claims. (In reality, it's just an opinion.)

There appear to be no particular self-stabilising processes to the general mechanism, though I take on board that some self-organisation is hoped for and that resistance to circumferential perturbations by mechanisms at the edge is speculated. I don't really see that myself. In fact, I think the system would actually benefit from gimballing vorticity (i.e. rotation of the reaction volume in multiple axes simultaneously) and it may well take on such rotations anyway if there is continuous ion and electron injections and due to the asymmetries that will be inevitable. Hence, experimentation of a small and incrementing nature seems to me to now be the only realistic way forward to establish evidence of the basic modes of operation, and the project does appear to be getting as much development funding as it can realistically use. Any call for greater funding would only occur if there were inappropriate jumps being attempted in the stages of required experimentation. I do not believe the scaling laws generated for Polywell carry much credibility and certainly not enough that they should influence decisions over funding.

Theoretical machinations on further potential complications or actual modal behaviour seems futile without diagnostics and results of real substance and repeatable quantity and quality that can usefully inform such a debate.

all the best,

Chris MB.

[IntLibber]

ya Return On Investment is what decides go or no go on any energy project, either production or conservation. When I was in the conservation business, if your proposal didnt have a ROI of less than two years, the utility wouldnt provide any funding for it, or less than typical.

That means capital invested: equipment, labor installation cost, plus remaining energy consumption, ongoing maintenance costs vs savings in energy consumption and, if you are lucky, maintenance costs as well.

So, I made this retrofit kit for exit signs, reduced energy consumption from 40w to .31 w, zeroed out maintenance costs for 30 years. Cost was $65US plus $10 installation cost, saved $3000 US over 30 years (at .07/kwh).

Now, we saved 99.44% of the energy consumed by 2x20w incandescent bulbs. Our competition was typically 15w compact fluorescent retrofit kits that cost $15 + $10 to install. So they saved 60% of the energy for 1/3 the cost of our product, but only lasted two years. Their ROI was 1 year, ours was as I recall 6 months.

Building owners bought the CF product cause the utility rebate (coming from DoE tax dollars) was typically $25, which covered 100% of the cost of the CF and installation, but only 1/3 of our cost, so the building owner would have to invest zero themselves in the CF solution.

Now, obviously, the utilities should have scaled the rebate based on the amount of savings, and obviously the smart building owner would value the maintenance savings we provided (Boeing was one such), but most building owners werent that smart, and only a few utilities were smart about scaling the rebate because most just ran off the DoE playbook.

Flat rebates (from tax subsidies) resulted in less actual energy conserved than if rebates were based on market factors instead. However in both cases, the return on investment had to be significantly shorter a period than the life cycle of the device.

A ROI that is half the life cycle means a 100% lifetime return on investment. If that life cycle is 10 years, thats a 10% return. 20 years means 5%. a 40 year nuke plant license with a 100% lifetime ROI means a 2.5% annual ROI.

Now, capital wants the highest return possible. The higher the return, the more capital that would be available for your project.

Renewable energy, be it wind, solar, nuclear, hydro, tidal, all are extremely capital intense endeavors. Typically 75% of the lifetime costs, or more, are in the capital invested in building the facility in the first place. Fossil fuels run about 20-25%, with the rest being the fuel and maintenance costs, etc.

When interest rates are high, power producers want to minimize capital costs, so fossil fuel production has a market advantage. Renewables depend upon low interest rates to become feasible, which is typically why large dams have historically been government built, and most other technology demonstrator plants for other renewables are also government subsidized.

Now, with interest rates at historical lows, this is a fantastic time to invest in renewables because capital costs will be greatly minimized over the lifetime of the facility. A 2.5% annual return is still significantly below, for instance, mortgage rates. It is, however, very decent for government bond yields at the present time.

So, even with todays very low interest rates, you will still need a 100% life time return (counting capital invested plus all lifetime operating costs). To do so commercially means you need a 300-400% lifetime return on investment, hence why you need those multiples.

[MSimon]

chris,

You outrank me militarily. On the knowledge front (the object in question here) the ranks are reversed.

And out of sentiment Navy Men get extra points from me. Even Engineering Apprentices.

You will have to tell us a sea story or two (in General). I always liked sea stories. And the traditions of the Royal Navy. ;-)

[MSimon]

chris,

I was discussing the instability problem with some one on this board a while back and suggested that the beams were the instability.

We can infer this from the fact that the beams naturally form and that without any inducement they oscillate.

The person who was discussing it with me thought that the idea might have some merit.

It has been my opinion for quite some time that Bussard was taking advantage of the natural reactions of a plasma rather than fighting them ala ITER/Tokamaks.

[KitemanSA]

What we need is an alpha receiver.

The State of the Art in Hadron Beam Cooling:
https://wiki.ornl.gov/sites/icns/HB%202 ... /Prost.ppt

I looked thru the linked .ppt but I guess I just don't get it. It seems to be talking of spending hours over tens of meters to bunch up a hadron beam, but I just can't equate that to converting an alpha spray into direct current power. There has got to be an easier way.

Perhaps I'll track down the 1980s era report Dan Tibbets mentioned in his following post.

[alexjrgreen]

The State of the Art in Hadron Beam Cooling:
https://wiki.ornl.gov/sites/icns/HB%202 ... /Prost.ppt

I looked thru the linked .ppt but I guess I just don't get it.

My apologies, I should have been clearer. On page 30 an RF cavity is used to recover energy from 10 MeV protons.

Earlier in this thread we discussed a NASA paper which Aero found last year that used beam power tube technology to recover energy from alpha particles (page 100): http://ntrs.nasa.gov/archive/nasa/casi. ... 005651.pdf

[alexjrgreen]

As a past Research Fellow in Computational Electro-magnetics

My research was on using modelling to predict sensitivity in systems and to understand when the 'theory' and a consequent electromagnetic 'model' create an unrealistic simulation of a real system.

The guys here working to simulate a polywell would really have appreciated your help...

[93143]

As a past Research Fellow in Computational Electro-magnetics

Okay. Does that mean Ph.D.? It usually does, and I'm still working on mine...

If not, it implies a nonstandard education (MSimon is a good example of this; apparently he used to say he wasn't qualified for the work he was doing). This isn't necessarily a bad thing, but it makes your unusual comments in our previous argument on electrostatics just a little less mystifying; there can be holes in a nonstandard education, particularly in terms of basic principles...

And yes, this can lead to unique perspectives that succeed where others fail. I just wish you were a little more interested in the 'succeed' part re: Polywell...

(I really hate that expression 'expert'!)

(1) I didn't intend to specifically classify myself as an expert; in this field I'm not. Art Carlson (for example) is. So is rnebel. That sentence was intended to be general.

(2) Why? In some areas I can see it, but physics?

of course that is only a subjective opinion though it may hold some weight on this forum as this kind of background seems to permit 'rights' to make such claims. (In reality, it's just an opinion.)

Have you ever read "The Cult of the Amateur"? Not all opinions are equal. If a random guy posts his "gut feeling", we have no obligation to give it any credence at all. If said random guy posts theoretical reasoning to back up his thesis, anyone who understands the reasoning can take it as seriously as it deserves. You have done this on various issues, but what annoys people is that you haven't considered the possibility that we already thought of the issue in question and reasoned our way to "we aren't sure yet". No one here assumes the Polywell will work.

[This is also why threads tend to get off topic and/or ad hominem around here. We've hashed it out pretty much as far as we can, and are getting antsy waiting for more experimental results.]

If someone who is known to have significant experience in a related field posts his "gut feeling" without physical reasoning, it carries more weight than it would if no background were available, simply because the person saying it can be expected to know what he's talking about (it's distressing how many people on the Internet have no idea what they're talking about). It is, as you say, still just an opinion, although from our perspective the chance of it being wildly off base is lower.

In other words, if you post something like this on the Internet, you have to say WHY you believe it. If the "why" is physical reasoning, great. If it's just a qualification, well... proof from authority is a logical fallacy, but argument from authority, done correctly, is not (don't rush off to Wikipedia to try to counter this; pay attention to the words I'm contrasting).

Also, the reason I asked, originally, was not because you had made unsupported statements; it was because I couldn't understand why you were saying the things you were about electrostatics.

I do not believe the scaling laws generated for Polywell carry much credibility and certainly not enough that they should influence decisions over funding.

They may ignore as-yet-unknown scale-dependent confinement and/or stability effects, but the base scaling laws are pretty fundamental. The way the achievable magnetic field scales with the coil size in this device results in the 7th-power gross output scaling law regardless of the details of the plasma. The 5th-power gain scaling is a bit less obvious, but something would have to go pretty badly wrong for the estimate to be out by more than a single power, and 4th-power gain scaling is still workable.

Now the question is, where are the detected neutrons from? ie: What exactly can we expect to scale at those powers? Beam-background scales a lot slower, which is why everyone's so worried about it...



In the interests of full disclosure:

I have an M.Sc. in mechanical engineering from the University of Alberta. The topic was microscale droplet deformation in an electric field, with focus on dynamic effects. It was supposed to be a prelude to modelling of electrowetting actuators in lab-on-a-chip devices, but since I started from scratch I didn't get that far. I presented my research at ICMENS 2004 and ICMENS 2005 (there was no paper in 2005 because I was invited after the deadline had already passed). I got two peer-reviewed publications out of my thesis, not counting the 2004 conference paper. The model allowed both perfect and leaky (Taylor) dielectric fluids. I also managed to get the full Navier-Stokes/Poisson/Nernst-Planck moving boundary system working for the full electrokinetic problem, and matched the theoretical steady-state small-deformation limit result to within 0.01%, but due to time constraints it didn't make it into my thesis.

I am currently in the second year of a Ph.D. program at the University of Toronto Institute for Aerospace Studies and have just passed my qualifying exam. My current work is in CFD modelling of high-temperature (superheated/near-critical/supercritical) jet fuel sprays. I just can't get away from these *&#% droplets, seemingly...

So basically my strongest point is fluid mechanics, especially CFD, and my second strongest point is electrostatics.

Also, I've been a fan of fusor technology since 1998 or so (yes, Tom Ligon, I'm looking at you...).

Also, the levelset method is freaking useless on a microcomputer...

[alexjrgreen]

I also managed to get the full Navier-Stokes/Poisson/Nernst-Planck moving boundary system working for the full electrokinetic problem, and matched the theoretical steady-state small-deformation limit result to within 0.01%

Can you do that with Quaternions?

[93143]

I also managed to get the full Navier-Stokes/Poisson/Nernst-Planck moving boundary system working for the full electrokinetic problem, and matched the theoretical steady-state small-deformation limit result to within 0.01%

Can you do that with Quaternions?

Do we have a wiseass here? (Okay, maybe I went a little off the deep end with those details...)

I've never worked with quaternions. I've never needed them. I have only the barest notion of what they are. My knowledge of the quaternion form of Maxwell's equations is purely hearsay.

[alexjrgreen]

I also managed to get the full Navier-Stokes/Poisson/Nernst-Planck moving boundary system working for the full electrokinetic problem, and matched the theoretical steady-state small-deformation limit result to within 0.01%

Can you do that with Quaternions?

Do we have a wiseass here? (Okay, maybe I went a little off the deep end with those details...)

I've never worked with quaternions. I've never needed them. I have only the barest notion of what they are. My knowledge of the quaternion form of Maxwell's equations is purely hearsay.

Guilty as charged

Actually I was serious: http://www.springerlink.com/content/7667703200j8380p/

Quaternions keep track of energy and momentum at the same time, so if you're willing to take the harder road you'll get better answers.

Doug Sweetser has a nice introduction here: http://www.quaternions.com

[IntLibber]

I also managed to get the full Navier-Stokes/Poisson/Nernst-Planck moving boundary system working for the full electrokinetic problem, and matched the theoretical steady-state small-deformation limit result to within 0.01%

Can you do that with Quaternions?

Oh god, not quats.

[alexjrgreen]

Oh god, not quats.

"We choose to go to the moon in this decade and do the other things, not because they are easy, but because they are hard..."