Subject: Re: Where can I find more information on Cold Fusion?
From: pusch@mcs.anl.gov (Gordon D. Pusch)
Date: May 19 1996
Newsgroups: sci.physics.fusion

In article <4ndbji$451@news.fm.intel.com> brauchfu@frx449.intel.com (Brian Rauchfuss - PCD) writes: > It looks like it would be more than just good engineering will be > needed to produce practical muon fusion. The number of fusions per > muon is limited by the sticking coefficient: the odds that the muon > will be absorbed by one of the reaction products. The best measured > value of this is 0.4%, which will produce 250 fusions/muon or > 4.4GeV/muon. The energy needed to produce each muon looks like it > would be a minimum of 4-6GeV. When I've looked at the various breakeven calculations'' on \mu-cat fusion, I've found that there is usually a very surprising omission: the energy the muon beam itself deposits in the target !!! =Much= smaller energy contributions are often taken into account (e.g., neutron capture by the lithium blanket), but simple heating of the target is usually forgotten, for some bizarre reason... I've found that, by taking this factor into account, \mu-cat fusion can =already= exceed breakeven; however, the recirculated power is usually annoyingly large compared to power out to the electrical grid (about 3--5 times as large, according to my estimates). Despite this rather high recirculated power, the overall cycle efficiency is not too bad (roughly comparable to conventional fission reactors); however, I would expect that needing 4--6 MW electrical generating capacity for each megawatt out to the grid probably represents an unacceptably large capital investment... :-( (My primary assumptions in this calculation are: 1.) that the fusion gain peaks at around 1100 Kelvin, as in published calculations; 2.) that a driving-accelerator efficiency of at least 60% can be achieved; and 3.) that an electrical efficiency of at least 80% of the Carnot limit ( 72% = (1100 - 300) / 1100 ) can be achieved; everything else follows the estimates by Elasser, and/or that Russian who published in _Nature_ in '79(?) whose name I can never remember, beyond thinking it begins with Ya').) > One or the other of these numbers needs to be improved by a factor > of 10 (at least) to make it practical. What is really needed is a > clever, low-power way of making muons. Anybody? Using Bogdan Maglich's migma'' self-colliding beam concept can significantly increase the muon production efficiency, by eliminating target losses. (Not my idea; it was published in the 2nd International Workshop on Aneutronic Fusion; proceedings published as a single issue of _Nuclear Instrumentation and Methods_ in the late '80s; sorry, I can't give you the exact reference, but it's at my office, not home...). Using tritons as the driver beam also helps, because the ratio of negative vs. positive muons produced is closely related to the ratio of neutrons vs. protons in the driver beam and target; hence, tritium on tritium'' yields more negative muons than any other collision... IMO, however, \mu-cat still suffers from all the =least= attractive aspects of DT fusion: high neutronicity; energy output primarily as high-energy neutrons that must be thermalized in order to convert them to useful energy; and a =very= high tritium inventory on-site (on the order of several tonnes --- and in gaseous form at high temperature, and under several =hundred= atmospheres of pressure, making the risk of accidental release even higher... :-( Gordon D. Pusch | Internet: <pusch@mcs.anl.gov> Math and C.S. Div., Bldg.203/C254 | FAX: (708) 252-5986 Argonne National Laboratory | Phone: (708) 252-3843 9700 South Cass Ave. | Argonne, IL USA 60439-4844 | http://www.mcs.anl.gov/people/pusch/ But I don't speak for ANL or the DOE, and they *sure* don't speak for =ME=...  Subject: Muon-catalyzed fusion (was Re: Where can I find more information on Cold Fusion?) From: pusch@mcs.anl.gov (Gordon D. Pusch) Date: May 20 1996 Newsgroups: sci.physics.fusion In article <v01530501adc58783d209@[204.17.242.77]> hheffner@anc.ak.net (Horace Heffner) writes: > >Originally-From: pusch@mcs.anl.gov (Gordon D. Pusch) > [snip] > >IMO, however, \mu-cat still suffers from all the =least= attractive > >aspects of DT fusion: high neutronicity; energy output primarily > >as high-energy neutrons that must be thermalized in order to convert > >them to useful energy; and a =very= high tritium inventory on-site > >(on the order of several tonnes --- and in gaseous form at high > >temperature, and under several =hundred= atmospheres of pressure, > >making the risk of accidental release even higher... :-( > > It seem to me you don't need the gas under high pressure. You could > accelerate T3+ ions in a vacuum toward plastic targets (panels) made > of C and T to generate the muons. You don't need to have the =target-gas= under pressure to =PRODUCE= the muons, but you ===DO=== need the D/T mix in the =reaction-chamber= under high pressure and temperature to maximize the reaction rate. The efficiency of \mu-cat fusion is currently estimated to be maximized at a temperature of ~1100 Kelvin, and a density approaching that of liquid hydrogen. I've yet to see a firm figure quoted on the corresponding pressure --- the ideal gas law breaks down pretty badly under such conditions, and I don't think the published tables go that high --- but I understand that it's on the order of several hundred atmospheres. Given that the whole process is only marginally above breakeven, I doubt if operating away from the peak efficiency should be considered, unless one has a *darned* good reason to do so... Gordon D. Pusch | Internet: <pusch@mcs.anl.gov> Math and C.S. Div., Bldg.203/C254 | FAX: (708) 252-5986 Argonne National Laboratory | Phone: (708) 252-3843 9700 South Cass Ave. | Argonne, IL USA 60439-4844 | http://www.mcs.anl.gov/people/pusch/ But I don't speak for ANL or the DOE, and they *sure* don't speak for =ME=...  From: pusch@mcs.anl.gov (Gordon D. Pusch) Newsgroups: sci.physics.fusion,sci.physics,sci.energy, alt.sci.physics.new-theories,sci.energy.hydrogen Subject: Re: Information on Migma Fusion Reactor Date: 08 Aug 1996 11:15:37 -0500 In article <32095D2C.2C96@datanet.ab.ca> James Curtis <jcurtis@datanet.ab.ca> writes: > I have been reading an interview transcript on Migma Fusion technology > aired by CBC in 1985. It is an interview with people from United > Sciences Incorporated. I also remember a magazine article on the very > same subject in a lesser known science magazine who's name escapes me. > The Physical Review Letters published an article on the 25 February '85 > which in a nut shell said the following: > > " Experiment with stored 0.7 mev ions--Observation of stability > properties of a non-thermal plasma: A large orbit non-thermal D+ > migma plasma with P sub theta equal to zero, and E ion equal to 0.7 > million electron volts was formed in the centre of a simple mirror > with densities n = 1E9 to 1E10 per cubic centimeter. Confinement > time was 20 to 45 seconds. Flute, negative mass and ion cyclotron > instabilities found in other mirrors at several orders of magnitude > lower N were not observed....." > > What I would like is get more current information and progress in the > development of this technology. Most anything information would be > appreciated. Maglich is still around; back in '91 or '92, he formed a new company, the Advanced Physics Corporation and Research Consortium,'' in collaboration with N. Rostoker of UC-Irvine (sorry, but they don't appear to have a web-page... :-). When I called Rostoker in late '92, he said that they had three Nobel-prize winners on the Board of Directors,'' but silly me, I forgot to ask who they were... :-/ For semi-recent publications by Maglich and collaborators, check out: Self-Colliding Systems for Aneutronic Fusion,'' N. Rostoker and B.C. Maglich, Comments on Plasma Phys., v.15, no.2 pp.105--120 (1992) Magnetic Fusion with High Energy Self-Colliding Ion Beams,'' N. Rostoker et.al., Phys.Rev.Lett., v.70, no.12, pp.1818--1821 (22 Mar 1993) and an entire issue of Nuclear Instruments and Methods'' [v. A271, pp. 1--235 (1988)] devoted to the proceedings of an International Symposium on the migma and other advanced'' and/or aneutronic'' fusion concepts. Some history: In 1982, Maglich achieved a world-record fusion triple product'' (density times energy-confinement-time times mean energy) of n \tau T = 4e14 keV sec cm^-3 --- a record that was not approached by a conventional tokamak until JET achieved 3e14 keV sec cm^-3 in 1987. (The triple-product is the relevant figure-of-merit for steady-state fusion-reactor operation; the more familiar Lawson ignition criterion'' is irrelevant to migmas since they are beam-driven, non-thermal, and do not ignite.'') Maglich's record was all the more remarkable in that it was achieved by a small company for a total expenditure of only US$ 2M
(all private).

Unfortunately, his first company, FEC, was forced to declare bankruptcy
after he made the mistake of trying to get an ERDA grant to augment his
private funds; the grant was rejected, and his investors abandoned him
because of the U.S. Gov't's official seal of DIS-approval... :-(

(BTW, his grant-proposal was rejected, not on its technical merits,
Tokamak'' and Laser-Inertial-Confinement'' approaches should be
funded. Migma was erroneously classified as a magnetic mirror machine,''
and ERDA had decided to phase out mirrors.'' When Maglich tried to
appeal this decision, the Gov't-convened Robson commission did a
negative statements, with no opportunity for rebuttal). A colleague
of mine let me read copies of the Robson report and FEC's response;
the Robson commission's misunderstanding of the principles behind
migma was very distressing...)

Gordon D. Pusch --- PostDoc currently Visiting (but =NOT= paid by!)

Math and C.S. Div., Bldg.203/C254   |  Internet: <pusch@mcs.anl.gov>
Argonne National Laboratory         |  FAX:      (708) 252-5986
9700 South Cass Ave.                |  Phone:    (708) 252-3843
Argonne, IL  USA  60439-4844        |  http://www.mcs.anl.gov/people/pusch/

I don't speak for ANL or the DOE, and they *sure* don't speak for =ME=...



From: carlson@ipp-garching.mpg.de (Arthur Carlson TOK )
Newsgroups: sci.physics.fusion,sci.physics,sci.energy,
alt.sci.physics.new-theories,sci.energy.hydrogen
Subject: Re: Information on Migma Fusion Reactor
Date: 08 Aug 1996 09:17:58 +0200

There was a review by Maglich in 1988, which is the most complete
description I have run across:

Nuclear Instruments and Methods in Physics Research A271 (1988) 13-36

More recently there has been some closely related nice work by Todd
Rider at MIT:

Fundamental Limitations on Plasma Fusion Systems Not in
Thermodynamic Equilibrium, Ph.D. Thesis, MIT Department of
Electrical Engineering and Computer Science, June 1995

Physics of Plasmas 2, 1853-1872 and 1873-1885 (June 1995)

He shows with very general arguments that no fusion scheme will work
which requires a plasma significantly removed from thermal
equilibrium. Since migma lives from a non-Maxwellian ion distribution
and cold electrons, it seems to be ruled out. He goes on to consider
advanced fuels and concludes that in the best case, you will still
have to deal with 5% of your energy in the form of neutrons.

(Followups have been trimmed to
sci.physics.fusion,sci.physics,sci.energy)
--
To study, to finish, to publish. -- Benjamin Franklin

Dr. Arthur Carlson
Max Planck Institute for Plasma Physics
Garching, Germany
carlson@ipp-garching.mpg.de
http://www.rzg.mpg.de/~awc/home.html



From: pusch@mcs.anl.gov (Gordon D. Pusch)
Newsgroups: sci.physics.fusion,sci.physics,sci.energy
Subject: Re: Information on Migma Fusion Reactor
Date: 08 Aug 1996 11:09:49 -0500

In article <pv2afw6fiop.fsf@s4awc.ipp-garching.mpg.de>
carlson@ipp-garching.mpg.de (Arthur Carlson TOK ) writes:

> There was a review by Maglich in 1988, which is the most complete
> description I have run across:
>
>   Nuclear Instruments and Methods in Physics Research A271 (1988) 13-36
>
> More recently there has been some closely related nice work by Todd
> Rider at MIT:
>
>   Fundamental Limitations on Plasma Fusion Systems Not in
>   Thermodynamic Equilibrium, Ph.D. Thesis, MIT Department of
>   Electrical Engineering and Computer Science, June 1995
>
>   Physics of Plasmas 2, 1853-1872 and 1873-1885 (June 1995)
>
> He shows with very general arguments that no fusion scheme will work
> which requires a plasma significantly removed from thermal equilibrium.
> Since migma lives from a non-Maxwellian ion distribution and cold
> electrons, it seems to be ruled out.

I believe I've read the _Phys.Plasm._ paper. If I recall correctly,
Rider uses Lawson Criterion'' type arguments to show that an
=IGNITED= plasma cannot =MAINTAIN ITSELF= in a state far from
equilibrium.  However, Migma is a non-ignition'' concept ---
instead, it functions as an energy amplifier:'' energy is
continuously input via the injector-beams into a migma-disk of
non-zero reactivity, and continuously extracted from the unreacted
fuel and reaction products that diffuse into the loss-cone'' using
direct conversion.'' If the gain'' of the migma-disk is large
enough that the recirculated power is acceptably small (e.g., less
than 10% of the power output), the migma is considered to be above
engineering breakeven,'' even though the migma hasn't ignited''
in the thermonuclear sense (alpha-particle self-heating equals energy
extracted). Ignition'' (Lawson criterion == density * confinement-time)
isn't relevant to migmas; instead, their performance depends on the
fusion triple product'' (FTP :== density * mean-energy * confinement-time).
Maglich claims that even his =OLD= migma experiments more than a decade ago
had FTPs that have only recently been exceeded by tokamaks...

Now, since the migma's loss-rate has a fairly sharp cutoff above the
passband energy'' (an alternating-gradient accelerator concept most
plasma-physicists would be unfamiliar with), the migma automatically
maintains its fuel in a non-maxwellian state; likewise, as shown in a
paper I'd have to dig up the reference on, the migma electrons radiate
their transverse kinetic energy on a timescale much shorter than the
fuel particles heat them; hence, they stay cold.'' Since the coulomb
scattering time for the fuel is longish compared to the slowing-down
time for the fuel-particles plowing through the background electrons,
the relevant energy confinement-time is the amount of time it takes
for the fuel to decelerate from the injection energy to the bottom of
the passband.'' Maglich =claims= that this time is long enough that
substantial fusion gain can be achieved. (Note that since the unreacted
fuel leaves the reactor at a well-defined energy (the passband bottom),
direct-conversion technology can recover its energy with high efficiency.
Likewise, the open'' field-configuration of the migma means that the
reaction-products leave the reactor before thermalizing; hence, they too
will have well-defined energies if the migma uses a 2-body to 2-body
reaction.)

> He goes on to consider advanced fuels and concludes that in the best
> case, you will still have to deal with 5% of your energy in the form
> of neutrons.

I don't remember reading this in the _Phys.Plasm._ paper; I'll have
to check it again. However, if it presupposes the same very general
assumptions'' as Rider's argument RE: non-maxwellian plasmas, I suspect
that it will again prove to be relevant to conventional'' fusion
reactors, but not migmas...

Gordon D. Pusch                     |  Internet: <pusch@mcs.anl.gov>
Math and C.S. Div., Bldg.203/C254   |  FAX:      (708) 252-5986
Argonne National Laboratory         |  Phone:    (708) 252-3843
9700 South Cass Ave.                |
Argonne, IL  USA  60439-4844        |  http://www.mcs.anl.gov/people/pusch/

But I don't speak for ANL or the DOE, and they *sure* don't speak for =ME=...



From: carlson@ipp-garching.mpg.de (Arthur Carlson TOK )
Newsgroups: sci.physics.fusion,sci.physics,sci.energy
Subject: Re: Information on Migma Fusion Reactor
Date: 09 Aug 1996 10:57:53 +0200

Thanks for the info. I found some more references from the last time
the topic came up in sci.physics.fusion, but none of them more recent
than 1978:

"The Migma principle of controlled fusion"
Bogdan C. Maglich
Nuclear Instruments and Methods III (1973), p 213-235

"An experimental model of migmacell"
Maglich, Mazrakis, Galayda, Rbinson, Lieberman, Weber, et al
Nuclear Instruments and Methods 120 (1974), p 308-319

"A study of the feasibility of fusion power wiht negligible neutron
production"
James Treglio
Nuclear Instruments and Methods 141 (1977), p 353 - 361

"Conditions for a boron fusion reactor in the MeV range"
James Treglio
Nuclear Instruments and Methods 144 (1977) 65 - 68

"Advanced fuel fusion application to manned space propulsion"
Roger Ho
Nuclear Instruments and Methods 144 (1977), p 69 - 72

"Unified criterion for proximity to controlled fusion"
Bogdan Maglich
Nuclear Instruments and Methods 144 (1977), p 77 - 80

"The 1976 status of the migma program of controlled fusion"
Bogdan Maglich
Nuclear Instruments and Methods 144 (1977), p 33 - 42

"Migmacell - A low-gain "driven" fusion power amplifier as an interim
energy source"
Bogdan C. Maglich
Nuclear Instruments and Methods 151 (1978), p 1 - 27
--
To study, to finish, to publish. -- Benjamin Franklin

Dr. Arthur Carlson
Max Planck Institute for Plasma Physics
Garching, Germany
carlson@ipp-garching.mpg.de
http://www.rzg.mpg.de/~awc/home.html



From: carlson@ipp-garching.mpg.de (Arthur Carlson TOK )
Newsgroups: sci.physics.fusion,sci.physics,sci.energy
Subject: Re: Information on Migma Fusion Reactor
Date: 09 Aug 1996 10:33:14 +0200
<pv2afw6fiop.fsf@s4awc.ipp-garching.mpg.de>
<phybjpvovp.fsf@freedom.mcs.anl.gov>
In-reply-to: pusch@mcs.anl.gov's message of 08 Aug 1996 11:09:49 -0500

In article <phybjpvovp.fsf@freedom.mcs.anl.gov> pusch@mcs.anl.gov (Gordon D. Pusch) writes:

> I believe I've read the _Phys.Plasm._ paper. If I recall correctly,
> Rider uses Lawson Criterion'' type arguments to show that an
> =IGNITED= plasma cannot =MAINTAIN ITSELF= in a state far from
> equilibrium.  However, Migma is a non-ignition'' concept ---
> instead, it functions as an energy amplifier:'' energy is
> continuously input via the injector-beams into a migma-disk of
> non-zero reactivity, and continuously extracted from the unreacted
> fuel and reaction products that diffuse into the loss-cone'' using
> direct conversion.'' If the gain'' of the migma-disk is large
> enough that the recirculated power is acceptably small (e.g., less
> than 10% of the power output), the migma is considered to be above
> engineering breakeven,'' even though the migma hasn't ignited''
> in the thermonuclear sense (alpha-particle self-heating equals energy
> extracted). Ignition'' (Lawson criterion == density * confinement-time)
> isn't relevant to migmas; instead, their performance depends on the
> fusion triple product'' (FTP :== density * mean-energy * confinement-time).
> Maglich claims that even his =OLD= migma experiments more than a decade ago
> had FTPs that have only recently been exceeded by tokamaks...

Lawson calculated the n*tau required to run a reactor as a function of
temperature. Obviously, this curve has a minimum at some temperature,
so n*tau has to be larger than the value at the optimum temperature.
He made a number of assumptions, including a thermal ion distribution.
If you allow arbitrary distributions, the number will look a little
better because you can put all your particles exactly at the peak
fusion cross section, but it won't change the picture much. (Does
somebody have time to calculate the condition on n*tau for thermal and
monoenergetic distributions for various reactions? It shouldn't be too
hard.) There are also some assumptions about conversion efficiencies
and recirculating power fraction involved, but changing these numbers
cannot change the requirement by more than a small factor. This
minimum n*tau is achieved at a particular temperature/energy. If you
move away from this optimum, you need a higher n*tau still.

Just as Lawson drew a curve for the required n*tau as a function of T,
one can draw a curve for n*tau*T as a function of T, which will also
have a minimum at some optimum T. This measure of performance is more
interesting than n*tau because it can be shown that the maximum power
density at a given pressure will be at this optimum T. This makes your
power plant more economical because it allows you to produce as much
power as possible in a given machine. As with n*tau, the exact minimum
value of n*tau*T depends on various assumptions, but the principle is
very general.

This is where I see migma pulling a PR fast one. n*tau*T is a good way
to compare performance for machines operating near the optimum
temperature/energy. Migma operates at a very high energy, far from the
optimum. In this regime, the n*tau*T required will be much higher than
for a tokamak operating at 10-20 keV. In short, neither the Lawson
criterion nor the limit on the triple product is relevant for migma,
except in the negative sense that it requires an n*tau and an n*tau*T
much higher than those required by more conventional configurations.

> Now, since the migma's loss-rate has a fairly sharp cutoff above the
> passband energy'' (an alternating-gradient accelerator concept most
> plasma-physicists would be unfamiliar with), the migma automatically
> maintains its fuel in a non-maxwellian state; likewise, as shown in a
> paper I'd have to dig up the reference on, the migma electrons radiate
> their transverse kinetic energy on a timescale much shorter than the
> fuel particles heat them; hence, they stay cold.'' Since the coulomb
> scattering time for the fuel is longish compared to the slowing-down
> time for the fuel-particles plowing through the background electrons,
> the relevant energy confinement-time is the amount of time it takes
> for the fuel to decelerate from the injection energy to the bottom of
> the passband.'' Maglich =claims= that this time is long enough that
> substantial fusion gain can be achieved. (Note that since the unreacted
> fuel leaves the reactor at a well-defined energy (the passband bottom),
> direct-conversion technology can recover its energy with high efficiency.
> Likewise, the open'' field-configuration of the migma means that the
> reaction-products leave the reactor before thermalizing; hence, they too
> will have well-defined energies if the migma uses a 2-body to 2-body
> reaction.)

The migma may indeed "automatically" have non-Maxwellian ions and cold
electrons. Todd Rider's point is that it costs gobs of power to
maintain this state, no matter how it happens.

> > He goes on to consider advanced fuels and concludes that in the best
> > case, you will still have to deal with 5% of your energy in the form
> > of neutrons.
>
> I don't remember reading this in the _Phys.Plasm._ paper; I'll have
> to check it again. However, if it presupposes the same very general
> assumptions'' as Rider's argument RE: non-maxwellian plasmas, I suspect
> that it will again prove to be relevant to conventional'' fusion
> reactors, but not migmas...

Sorry, I have to cite "private communication". I think the more
far-reaching conclusions are only in his thesis, which I ordered months
ago but have not yet received. It is true that he considered the
neutron question only after he had drawn his conclusions on the
necessity of thermal plasmas.

Disclaimer: I do not understand migma. It is one of those concepts
which is so far outside my range of experience that it is easily
possible that I am unconsciously making unwarranted assumptions.
Nevertheless, I feel obligated to critically apply what I think I
know.

--
To study, to finish, to publish. -- Benjamin Franklin

Dr. Arthur Carlson
Max Planck Institute for Plasma Physics
Garching, Germany
carlson@ipp-garching.mpg.de
http://www.rzg.mpg.de/~awc/home.html
`