Author Topic: micro-fusion work without fission trigger  (Read 16573 times)

Offline advancednano

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micro-fusion work without fission trigger
« on: 12/04/2008 05:41 PM »
http://nextbigfuture.com/2008/12/micro-fusion-for-space-propulsion-and.html

Micro-fusion work of Friedwardt Winterberg from the 1950's-1970s was
recently declassified [not sure when the declassification happened. It may have been some time ago. Classified status was mentioned in the paper but classified/declassified is not relevant]. Winterberg has several ideas for using micro-fusion without fission bomb triggers to generate nuclear energy or power spacecraft. Winterberg was proposing pure deuterium micro-explosions.

Proposed use of a super Marx generator to ignite a pure deuterium
thermonuclear micro-explosion. In a super Marx generator, N Marx
generators charge up N fast capacitors FC to the voltage V, which
switched into series add up their voltages to the voltage NV. The
proposed super Marx generator can reach what nature can do in
lightning. The high voltage in natural lightning is released over a
distance about 1 km, and the same is true for the super Marx
generator.

For a propulsion system to transport large payloads with short transit
times between different planetary orbits: a deuterium fusion bomb
propulsion system is proposed where a thermonuclear detonation wave is
ignited in a small cylindrical assembly of deuterium with a
gigavolt-multimegampere proton beam, drawn from the magnetically
insulated spacecraft acting in the ultrahigh vacuum of space as a
gigavolt capacitor.

For a cost effective lifting of large payloads into earth orbit: the
ignition is done by argon ion lasers driven by high explosives, with
the lasers destroyed in the fusion explosion and becoming part of the
exhaust.

If launched from the surface of the earth, one has to take into
account the mass of the air entrained in the fireball. The situation
resembles a hot gas driven gun, albeit one of rather poor efficiency.
Assuming an efficiency of 10%, about 100 kiloton explosions would be
needed to launch 1000 tons into orbit. It would be a cleaner and more
public relations friendly version of the Orion Nuclear Pulsed
Propulsion system.

« Last Edit: 12/04/2008 11:10 PM by advancednano »

Offline gospacex

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Re: Declassified micro-fusion work without fission trigger
« Reply #1 on: 12/04/2008 09:25 PM »
Unsure how to classify this. Is it bad enough to alert a moderator?

Offline advancednano

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Re: Declassified micro-fusion work without fission trigger
« Reply #2 on: 12/04/2008 10:15 PM »
Wikipedia entry for Friedwardt Winterberg.

Friedwardt Winterberg (born June 12, 1929) is a German-American theoretical physicist and research professor at the University of Nevada, Reno. With more than 260 publications and three books, he is known for his research in areas spanning general relativity, Planck scale physics, nuclear fusion, and plasmas. "His work in nuclear rocket propulsion earned him the 1979 Hermann Oberth Gold Medal of the Wernher von Braun International Space Flight Foundation and in 1981 a citation by the Nevada Legislature." Winterberg is well-respected for his work in the fields of nuclear fusion and plasma physics, and Edward Teller has been quoted as saying that he had "perhaps not received the attention he deserves" for his work on fusion. He is known for his ideas which lead to the development of GPS (Global Positioning System), his fusion activism, his first proposal to experimentally test Elsasser's theory of the geodynamo.


Gospacex: What is the problem that you have with the posting ?

Btw: Winterberg also was a doctoral student of Heisenberg (Heisenberg uncertainty Heisenberg) and also wrote very important papers for the Nerva rocket and early Z-pinch work etc...
« Last Edit: 12/04/2008 11:03 PM by advancednano »

Offline gospacex

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Re: micro-fusion work without fission trigger
« Reply #3 on: 12/04/2008 11:33 PM »
It just sounds very unprofessional.

"where a thermonuclear detonation wave is ignited in a small cylindrical assembly of deuterium with a gigavolt-multimegampere proton beam,"

Are you trying to impress 10 year old kids with these "gigavolts" and "multimegamperes"? Serious paper would rather explain how the beam is supposed to ignite the reaction...

"drawn from the magnetically insulated spacecraft acting in the ultrahigh vacuum of space as a gigavolt capacitor."

1. A design having potential difference in 10^9 volts is insane, even in the vacuum.
2. Capacitors are not even measured in volts!

Offline Robotbeat

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Re: micro-fusion work without fission trigger
« Reply #4 on: 12/05/2008 02:24 AM »

"where a thermonuclear detonation wave is ignited in a small cylindrical assembly of deuterium with a gigavolt-multimegampere proton beam,"

Are you trying to impress 10 year old kids with these "gigavolts" and "multimegamperes"? Serious paper would rather explain how the beam is supposed to ignite the reaction...

...

2. Capacitors are not even measured in volts!

Actually, a capacitor's voltage rating is more important than it's capacitance, since the total stored energy goes up with voltage squared, but only linearly with capacitance.

Laser-triggered fusion and electrical-discharge-triggered fusion ( http://en.wikipedia.org/wiki/Z_machine ) are two very viable ways to achieve above-break-even fission-less fusion, perhaps even more likely than the crazy giant ITER tokamak boondoggle. If you aren't familiar with the different approaches to achieving fusion (break-even or not), then I suggest you at the very least read up on your Wikipedia.

Arrogance isn't very attractive, my friend. When you're dealing with problems of such an enormous scale, you're going to use "big words" like gigavolt. This is the "Advanced Concepts" Forum and the text in question refers to real physics, unlike the "Chinese Impossible Drive."
« Last Edit: 12/05/2008 02:31 AM by Robotbeat »
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Offline gospacex

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Re: micro-fusion work without fission trigger
« Reply #5 on: 12/05/2008 09:19 AM »
Laser-triggered fusion and electrical-discharge-triggered fusion ( http://en.wikipedia.org/wiki/Z_machine ) are two very viable ways to achieve above-break-even fission-less fusion, perhaps even more likely than the crazy giant ITER tokamak boondoggle. If you aren't familiar with the different approaches to achieving fusion (break-even or not), then I suggest you at the very least read up on your Wikipedia.

And what to do if I am already familiar with the above, and more?

Quote
Arrogance isn't very attractive, my friend. When you're dealing with problems of such an enormous scale, you're going to use "big words" like gigavolt. This is the "Advanced Concepts" Forum and the text in question refers to real physics

Text in question is so vague that it is not even possible to distinguish whether it is talking about ion beam heating+compressing a fuel pellet in a hohlraum, or Z-machine-like magnetic field compression by way of high-power electrical discharge, or something else altogether.

You are probably right. I had to keep silent and let it sink without any comments.

Offline advancednano

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Re: micro-fusion work without fission trigger
« Reply #6 on: 12/05/2008 05:21 PM »
Links to the original papers.The original link had links to the original papers and the initial paragraphs were summarizing the claims in the papers.

Ignition of a Deuterium Micro-Detonation with a Gigavolt Super Marx Generator
http://au.arxiv.org/PS_cache/arxiv/pdf/0812/0812.0394v1.pdf

Deuterium microbomb Rocket Propulsion
http://au.arxiv.org/PS_cache/arxiv/pdf/0812/0812.0397v1.pdf

Ways Towards Pure Deuterium Inertial Confinement Fusion Through the Attainment of Gigavolt Potentials
http://au.arxiv.org/PS_cache/arxiv/pdf/0808/0808.1905v1.pdf

The attainment of ultrahigh electric potentials by suppressing the stepped leader breakdown of a highly charged conductor levitated in a spiraling Taylor flow opens up the possibility of order of magnitude larger driver energies for the ignition of thermonuclear reactions by inertial confinement. In reaching gigavolt potentials, intense 10**16 Watt, GeV ion beams become possible. Together with their large self-magnetic field, these beams should be powerful enough to launch a thermonuclear micro-detonation into pure deuterium, compressed and ignited by such beams. In high gain laser fusion the proton flash from the micro-explosion is likely to destroy the optical laser ignition apparatus, and it is not explained how to avoid this danger. The possible attainment of gigavolt potentials could make laser fusion obsolete.

Back in 1968, I [Winterberg] had proposed that ignition could be achieved by bombarding a small solid deuterium-tritium (DT) target with a 10 MJ – 10**15 Watt (10**7 Volt, 10**8 Ampere) relativistic electron beam drawn from a large Marx generator. Because the current is there well above the Alfvén limit, the beam would have to be propagated through a current neutralizing background gas, making it more difficult to focus it onto the target. More serious was the problem how to dissipate the beam energy within the small target. Because of these difficulties, a radically different approach was proposed at the same time. It was to charge up to gigavolt potentials a magnetically levitated, and in ultrahigh vacuum magnetically insulated conductor of metersize dimensions, acting like a high voltage capacitor. Discharging this capacitor would make possible the generation of intense gigavolt ion beams, as the discharging of a Marx capacitor bank makes possible the generation of intense MeV electron beams.

[presentation continues in the Winterberg papers]

Other Winterberg papers
http://au.arxiv.org/find/Computer+Science,Mathematics,Nonlinear+Sciences,Physics,Quantitative+Biology,Quantitative+Finance,Statistics/1/winterberg/0/1/0/all/3/0

Gospacex: Please explain why you believe that Winteberg is wrong about achieving gigavolt differences.

btw: are you wanting to debate the summary wording or do you want full copies of the papers cut and pasted into the forum ? I thought that this work was interesting and would be worth the commenters time to click through some links to see the details of the proposals. Especially when the source, Winterberg, is one of the key originators of the Z-pinch and laser triggered concepts with which Gospacex is already familiar with and more.
« Last Edit: 12/05/2008 05:21 PM by advancednano »

Offline advancednano

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Re: micro-fusion work without fission trigger
« Reply #7 on: 12/05/2008 05:40 PM »
There were three Winterberg proposals summarized in the first posting. Here is more details on the first.

1. using a series of Marx generators to ignite fusion in a ground based fusion power plant:

from Ignition of a Deuterium Micro-Detonation with a Gigavolt Super Marx Generator
http://au.arxiv.org/PS_cache/arxiv/pdf/0812/0812.0394v1.pdf

A 1.5 km long Super Marx generator, composed of 100x 15 m long high voltage capacitors each designed as a magnetically insulated coaxial transmission line. The coaxial capacitors/transmission lines are placed inside a large vacuum vessel. Each capacitor/transmission line is charged by two conventional Marx generators up symmetrically to 10 MV (± 5 MV). After charge-up is completed, the Marx generators are electrically decoupled from the capacitors/transmission lines. The individual capacitors/transmission lines are subsequently connected in series via spark gap switches (i.e. the „Super Marx generator), producing a potential of 1 GV.

Would it be not for electric breakdown, one could with a Marx generator reach in principle arbitrarily large voltages. According to Paschen's law, the breakdown voltage in gas between two plane parallel conductors is only a function of the product pd, where p is the gas pressure and d the distance between the conductors. For dry air at a pressure of 1 atmosphere the breakdown voltage is 3X10**4 V/cm, such that for a pressure of 100 atmospheres the breakdown voltage would be 3X10**8 V/cm. For a meter size distance between the conductors this implies a potential difference of the order 10**9 Volt. But as in lightning, breakdown occurs at much lower voltages by the formation of the “stepped leader”. The formation of a stepped leader though requires some time. Therefore, if the buildup of the high voltage is fast enough, breakdown by a stepped leader can be prevented. In a Marx generator the buildup of the voltage is not fast enough to reach a gigavolt. It is the idea of the super Marx generator how this might be achieved.

To obtain a short discharge time with a single Marx generator, the Marx generator charges up a fast discharge capacitor, discharging its load in a short time. This suggests using a bank of such fast discharge capacitors as the elements of a Marx generator, each one of them charged up by one Marx generator to a high voltage. One may call such a two-stage Marx generator a super Marx generator. If N fast capacitors are charged up by N Marx generators in parallel to the voltage V, the closing of the spark gap switches in the super Marx generator adds up their voltages to the voltages NV. In the super Marx generator, the Marx generators also serve as the resistors in the original Marx circuit. It is also advantageous to disconnect the Marx generators from the super Marx after its charge- up is completed. Fig. 3 shows the circuit of an ordinary Marx generator, in comparison to a super Marx shown in Fig. 4.

It is known, and used in electric power interrupters, that a high pressure gas flow can blow out a high power electric arc. Vice verse, it can be expected that a rapid gas flow can prevent breakdown. Therefore, just prior to the moment the super Marx generator is fired to one may place the super-Marx generator in a breakdown preventing gas brought into fast motion. An alternative is magnetic insulation in ultrahigh vacuum, by magnetically levitating, and by placing the capacitors of the super Marx in a strong axial magnetic field, insulating the super Marx against radial breakdown. For an axial magnetic field of 20,000 GaussB the magnetic insulation condition B[Gauss] ≥ E[esu] = 300E[Volt/cm], implies magnetic insulation up to 7X10**9Volt/cm. in addition, the current pulse, generated by the closing of the spark gap switches of the super Marx shown in Fig. 4, sets up an axial magnetic field. This too enhances magnetic insulation against radial breakdown. If the first few spark gap switches from the left, are triggered by pulsed lasers, the rise of the voltage at the remaining spark gap switches closes them in an avalanche moving fron the left to the right, leading to a chain of axial current plses moves from the left to the right. The magnitude of the azimuthal magnetic field by these current pulses can be estimated as follows: The energy e = (1/2) CV2, in each of the capacitors charged upto a voltage of ~ 10**7 Volt is assumed to be e = 10**7 Joule, which implies that C=2*10**-7Farad. The charge of each capacitor is Q = CV = 2 Coulomb. With the capacitors consisting of hollowmetallic cylinders of length l [cm], the discharge time is of the order,>= l/c (c velocity of light). Assuming that ,10**3cm one has 10**-7 seconds, implying a current, I= Q/ ~ 2X10**7 Ampere. At a radius of the cylinder about R 2X10**3cm, the magnetic field at this radius is B = 0.2I/R ~ 10**4 Gauss, sufficiently strong to insulate the (in the vacuum levitated) high voltage capacitors up to 6X10**3V/cm.

The high voltage end of the super Marx has to charge up a magnetically insulated Blumlein transmission line, delivering the GeV proton beam to the deuterium target. The magnetic insulation there can be made by making the Blumlein from co-axial superconducting toruses, as explained in my 1968 Physical Review paper

By connecting the high voltage terminal of the super Marx generator to a Blumlein transmission line, a very high voltage pulse with a fast rise time can be generated. At the envisioned very high voltages one can make a controlled breakdown in a gas, or liquid, generating an ion beam below the Alfvén limit. At these high voltages ion beams are favored over electron beams, because electron beams are there above the Alfvén limit. To assure that all the ions have the same charge to mass ratio, the gas or liquid must be hydrogen or deuterium, otherwise the beam will spread out axially, losing its maximum power.
Instead of making the breakdown in hydrogen gas, one may let the breakdown happen along a thin liquid hydrogen jet, establishing a bridge between the high voltage terminal of the Blumlein transmission line and the thermonuclear target.

Note: gigavolt references and million of amperes etc... are all from the Winterberg papers, which does also seem to explain how the reaction is supposed to be ignited.
« Last Edit: 12/05/2008 05:51 PM by advancednano »

Offline advancednano

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Re: micro-fusion work without fission trigger
« Reply #8 on: 12/05/2008 05:48 PM »
The second was a proposal for creating fusion on for spacecraft propulsion in vacuum.


Summarized from Deuterium microbomb Rocket Propulsion
http://au.arxiv.org/PS_cache/arxiv/pdf/0812/0812.0397v1.pdf

For a propulsion system to transport large payloads with short transit times between different planetary orbits: a deuterium fusion bomb propulsion system is proposed where a thermonuclear detonation wave is ignited in a small cylindrical assembly of deuterium with a gigavolt-multimegampere proton beam, drawn from the magnetically insulated spacecraft acting in the ultrahigh vacuum of space as a gigavolt capacitor. Note: This paper was presented in part at the NASA-JPL-AFRL 2008 Advanced Space Propulsion Workshop.

With no deuterium-tritium (DT) micro-explosions yet ignited, the non-fission ignition of pure deuterium (D) fusion explosions seems to be a tall order. An indirect way to reach this goal is by staging a smaller DT explosion with a larger D explosion. There the driver energy, but not the driver may be rather small.

Winterberger claims that the generation of GeV potential wells, made possible with magnetic insulation of conductors levitated in ultrahigh vacuum, has the potential to lead to order of magnitude larger driver energies. It is the ultrahigh vacuum of space by which this can be achieved. And if the spacecraft acting as a capacitor is charged up to GeV potentials, there is no need for its levitation.

The spacecraft is positively charged against an electron cloud surrounding the craft, and with a magnetic field of the order 10,000 Gauss, easily reached by superconducting currents flowing in an azimuthal direction, it is insulated against the electron cloud up to GeV potentials. The spacecraft and its surrounding electron cloud form a virtual diode with a GeV potential difference. To generate a proton beam, it is proposed to attach a miniature hydrogen filled rocket chamber R to the deuterium bomb target, at the position where the proton beam hits the fusion explosive. A pulsed laser beam from the spacecraft is shot into the rocket chamber, vaporizing the hydrogen, which is emitted through the Laval nozzle as a supersonic plasma jet. If the nozzle is directed towards the spacecraft, a conducting bridge is established, rich in protons between the spacecraft and the fusion explosive. Protons in this bridge are then accelerated to GeV energies, hitting the deuterium explosive. Because of the large dimension of the spacecraft, the jet has to be aimed at the spacecraft not very accurately.

Offline advancednano

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Re: micro-fusion work without fission trigger
« Reply #9 on: 12/05/2008 06:15 PM »
Third Winterberg proposal Deuterium Micro-explosive Space Launch Systems

Summarized from Deuterium microbomb Rocket Propulsion
http://au.arxiv.org/PS_cache/arxiv/pdf/0812/0812.0397v1.pdf

For a cost effective lifting of large payloads into earth orbit: the ignition is done by argon ion lasers driven by high explosives, with the lasers destroyed in the fusion explosion and becoming part of the exhaust.

If launched from the surface of the earth, one has to take into account the mass of the air entrained in the fireball. The situation resembles a hot gas driven gun, albeit one of rather poor efficiency. Assuming an efficiency of 10%, about 100 kiloton explosions would be needed to launch 1000 tons into orbit. It would be a cleaner and more public relations friendly version of the Orion Nuclear Pulsed Propulsion system.

Winterberg suggests an ultraviolet argon ion laser is used as a trigger. However, since argon ion lasers driven by an electric discharge have a small efficiency, he suggested a quite different way for its pumping where the efficiency can be expected to be quite high.  It was proposed to use a cylinder of solid argon, surrounding it by a thick cylindrical shell of high explosive. If simultaneously detonated from outside, a convergent cylindrical shockwave is launched into the argon. For the high explosive one may choose hexogen with a detonation velocity of 8 km/s. In a convergent cylindrical shockwave the temperature rises as r -0.4, where r is the distance from axis of the cylindrical argon rod. If the shock is launched from a distance of ~1 m onto an argon rod with a radius equal to 10 cm, the temperature reaches 90,000 K, just right to excite the upper laser level of argon. Following its heating to 90,000 K the argon cylinder radially expands and cools, with the upper laser level frozen into the argon. This is similar as in a gas dynamic laser, where the upper laser level is frozen in the gas during its isentropic expansion in a Laval nozzle. To reduce depopulation of the upper laser level during the expansion by super-radiance, one may dope to the argon with a saturable absorber, acting as an “antiknock” additive. In this way megajoule laser pulses can be released within 10 nanoseconds. A laser pulse from a small Q-switched argon ion laser placed in the spacecraft can then launch a photon avalanche in the argon rod, igniting a DT micro-explosion

Offline Lampyridae

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Re: micro-fusion work without fission trigger
« Reply #10 on: 12/11/2008 03:02 AM »
I've read similar proposals for Z-pinch, explosives-pumped microfusion devices (something like 10t yield / pulse). Actually, the name Winterberg rings a bell. I think it was one of his earlier papers?

Some very interesting ideas here. I'd thought about sacrificial lasers, but didn't know how to go about it cheaply (becoming part of the exhaust! oh well, most rocket stages are expendable anyway...). Thanks for posting, advancednano.

>EDIT<

Gigavolt differences were proposed for electrostatic shielding; unfortunately the structures had to be very large to take advantage of this, since the breakdown voltages were way above the vacuum breakdown potential at small scales. So concentric shells a few hundred metres across were envisioned, to stop solar wind. Heh, and now we "know" we can stop solar wind with just a big magnet.
« Last Edit: 12/11/2008 03:25 AM by Lampyridae »
SKYLON... The League of Extraordinary Gentlemen's preferred surface-to-orbit conveyance.

Offline drbuzz0

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Re: micro-fusion work without fission trigger
« Reply #11 on: 03/25/2009 04:06 PM »
This sounds like just basic IEC fusion which is not at all a new concept.  Basically the idea is to use enormous arrays of pulsed lasers or possibly a giant capacitor bank to ignite a tiny microsphere of fusion fuel.   It's not that much different than an H-bomb in that rather than a continuous active confinement system it just tries to compress the fuel with enough energy to ignite it.

It's theoretically possible, but it's a very tough nut to crack.  The National Ignition Facility has been working to achieve this goal and it is absolutely enormous in size and has cost billions to construct.

https://lasers.llnl.gov/

http://zpinch.sandia.gov/

Offline GI-Thruster

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Re: micro-fusion work without fission trigger
« Reply #12 on: 03/26/2009 02:39 PM »
This really does sound like electrostatic inertial confinement as in Bussard and Lerner.  Bussard gets lots of press, Lerner not so much:

http://lawrencevilleplasmaphysics.com/

http://lawrencevilleplasmaphysics.com/

except that Bussard and Lerner are both talking about B11 reactions instead of deuterium, which is a much nicer reaction though requiring much higher temperatures.  Note Lerner was claiming to have reached these while all the world was saying this was impossible. . .right up until Z-Pinch did the same.

BTW, Z-Pinch is not cutting edge here.  It fires once and is done.  If you want to demonstrate a real technology, you need continuous pulsed operation, the same requirement that makes fusion bomb rockets completely impractical.  Note the silliness that one could use deuterium bombs to launch into orbit.  Do you have any idea what the exhaust of such a scheme entails?

Bombs to make rockets=a really bad idea.

Offline drbuzz0

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Re: micro-fusion work without fission trigger
« Reply #13 on: 03/28/2009 03:40 PM »
This really does sound like electrostatic inertial confinement as in Bussard and Lerner.  Bussard gets lots of press, Lerner not so much:

http://lawrencevilleplasmaphysics.com/

http://lawrencevilleplasmaphysics.com/

except that Bussard and Lerner are both talking about B11 reactions instead of deuterium, which is a much nicer reaction though requiring much higher temperatures.  Note Lerner was claiming to have reached these while all the world was saying this was impossible. . .right up until Z-Pinch did the same.

the B11 reaction has advantages but it also means that you need a much much higher energy levels to produce.  The lack of high energy neutron radiation could be an advantage (or a disadvantage in some circumstances, like where neutrons are used to drive a secondary reaction).

Right now, we're at the point where getting any fusion reaction to consistently produce energy in a controlled manner would be a huge step.   We need to get it to work at all before we can start to talk about optimizing the reaction.

Bussard's design is very interesting and yes, it may have some real potential.   Lets just not put the cart infront of the horse here, we're going to need to make some huge advances before it becomes a realistic means of spaceflight propulsion.

I honestly don't know enough about Lerner's concept to really judge it, but I'm sure it's not ready for primetime yet.  If it was, I wouldn't be paying as much for electricity.

BTW, Z-Pinch is not cutting edge here.  It fires once and is done.  If you want to demonstrate a real technology, you need continuous pulsed operation, the same requirement that makes fusion bomb rockets completely impractical. 
The Z-pinch and all other such systems are nowhere near the kind of technology you'd need for space flight propulsion, that's clear.   It would have to be made to work reliably on the ground at least once before it could have the potential to be considered for space flight.   We're not even there yet.   Then of course you have not only the fact that it needs to be capable of repeated operation, but it also needs to be a reasonable size and mass.


Note the silliness that one could use deuterium bombs to launch into orbit.  Do you have any idea what the exhaust of such a scheme entails?

No more harmful than the h-bombs we were setting off left and right during the hayday of atmospheric testing in the 1950's and early 1960's.

Offline nomadd22

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Re: micro-fusion work without fission trigger
« Reply #14 on: 03/29/2009 04:40 PM »
 "Do you have any idea what the exhaust of such a scheme entails?"

 Do you? The bad stuff from H-bombs comes mostly from the fission triggers and uranium sheaths in the fission-fusion-fission bombs the Russians like. Fusing deuterium is fairly clean.
 Compared to the crap that solid boosters put out Deuterium fusion would probably be fairly benign.
« Last Edit: 03/29/2009 04:41 PM by nomadd22 »

Offline kevin-rf

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Re: micro-fusion work without fission trigger
« Reply #15 on: 03/30/2009 12:01 AM »
"Do you have any idea what the exhaust of such a scheme entails?"

 Do you? The bad stuff from H-bombs comes mostly from the fission triggers and uranium sheaths in the fission-fusion-fission bombs the Russians like. Fusing deuterium is fairly clean.

And US/Chinese/French/British bombs don't rely on a similar integrated fission/fusion reaction and are not equally messy? What percentage of an H bomb's bang actually comes from fusion again?

Now if you have a way to release large amounts of fusion energy that does not require a fission trigger. Well I'm sure Mr. Nobel will be knocking, along with Mr. Bond, and Mr. Putin, ect ect...
If you're happy and you know it,
It's your med's!

Offline nomadd22

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Re: micro-fusion work without fission trigger
« Reply #16 on: 03/30/2009 12:23 AM »
"Do you have any idea what the exhaust of such a scheme entails?"

 Do you? The bad stuff from H-bombs comes mostly from the fission triggers and uranium sheaths in the fission-fusion-fission bombs the Russians like. Fusing deuterium is fairly clean.

And US/Chinese/French/British bombs don't rely on a similar integrated fission/fusion reaction and are not equally messy? What percentage of an H bomb's bang actually comes from fusion again?

Now if you have a way to release large amounts of fusion energy that does not require a fission trigger. Well I'm sure Mr. Nobel will be knocking, along with Mr. Bond, and Mr. Putin, ect ect...
  If you want to act like a jerk you might want to read the statement first and do five minutes of research if you don't understand what fission/fusion/fission means. The Soviets were the only ones who deployed warheads that were wrapped in Uranium sheaths. The fusion reaction triggered a second fission reaction giving them a cheap way to double the power of the explosion. It also caused about a tenfold increase in long lived fallout products.

Offline kevin-rf

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Re: micro-fusion work without fission trigger
« Reply #17 on: 03/30/2009 01:03 AM »
Just to be a devils advocate and a real jerk, I like this section from a wiki page ( http://en.wikipedia.org/wiki/Nuclear_weapon_design )

Quote

Clean bombs
 
Bassoon, the prototype for a 3.5-megaton clean bomb or a 25-megaton dirty bomb. Dirty version shown here, before its 1956 test.

On March 1, 1954, America's largest-ever nuclear test explosion, the 15-megaton Bravo shot of Operation Castle at Bikini, delivered a promptly lethal dose of fission-product fallout to more than 6,000 square miles (16,000 km2) of Pacific Ocean surface.[25] Radiation injuries to Marshall Islanders and Japanese fishermen made that fact public and revealed the role of fission in hydrogen bombs.

In response to the public alarm over fallout, an effort was made to design a clean multi-megaton weapon, relying almost entirely on fusion. Since the energy produced by fission is essentially free, using the vital tamper as a source of extra energy the clean bomb needed to be much larger for the same yield. For the only time, a third stage, called the tertiary, was added, using the secondary as its primary. The device was called Bassoon. It was tested as the Zuni shot of Operation Redwing, at Bikini on May 28, 1956. With all the uranium in Bassoon replaced with a substitute material such as lead, its yield was 3.5 megatons, 85% fusion and only 15% fission.

On July 19, AEC Chairman Lewis Strauss said the clean bomb test "produced much of importance . . . from a humanitarian aspect." However, two days later the dirty version of Bassoon, with the uranium parts restored, was tested as the Tewa shot of Redwing. Its 5-megaton yield, 87% fission, was deliberately suppressed to keep fallout within a smaller area. This dirty version was later deployed as the three-stage, 25-megaton Mark-41 bomb, which was carried by U.S. Air Force bombers, but never tested at full yield.

As such, high-yield clean bombs were a public relations exercise. The actual deployed weapons were the dirty version, which maximized yield for the same size device.

Sadly, The real design of bombs as far as those of us in the public is concerned is as much factual as fiction.
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Offline nomadd22

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Re: micro-fusion work without fission trigger
« Reply #18 on: 03/30/2009 11:43 AM »
 Hey. Don't tell me how to be a jerk. I have more awards than Howard Stern.
 One of the reason some of those theoretical designs never saw serious development was the ridiculous difficulty in predicting what would go on in those multiple, near lightspeed shockwave fission/fusion messes. A nanosecond timing error or sub micron shaping error could make for one messy fizzle.

 I was mostly referring to the hypothetical method of fusing deuterium the thread was about. It seems a little sci-fi, but I do remember some unexpectedly spectacular results in some Los Alamos Z-pinch experiments, so who knows? It doesn't seem to likely those devices would ever be used in atmospheric flight, but who knows what the social/political climate might be like in 50 years or so.

Offline kevin-rf

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Re: micro-fusion work without fission trigger
« Reply #19 on: 03/30/2009 12:58 PM »
Yeah it would be great. Getting large amounts (more than you put in) of energy out of fusion (without a fission trigger) is just what? 50 years beyond the state of the art at this point... Z Pinch, Bussard, Laser implosion are great stepping stones... Like they say, this is a tough titanium coated nut to crack.
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