Half a croissant, on a plate, with a sign in front of it saying '50c'
h a l f b a k e r y
If you need to ask, you can't afford it.

idea: add, search, annotate, link, view, overview, recent, by name, random

meta: news, help, about, links, report a problem

account: browse anonymously, or get an account and write.



Cold Fusion Rocket Engine

Inertial Confinement Fusion with LESS squeeze
(+2, -2)
  [vote for,

This Idea can only work if notions presented elsewhere, about how conduction-band electrons in a metal can allow "bare" deuterium nuclei to closely approach each other, is true.

The key to this Idea is the realization that "conduction band electrons" don't have to be the ones found in palladium or titanium.

Did you ever hear of "metallic hydrogen" before? (see link)

This is an "allotrope" of hydrogen (a unique way in which atoms of just one element can connect to each other, the way ozone is an allotrope of oxygen), and theorists are quite certain that it CAN exist, especially in places like the interior of Jupiter, although it is difficult to say for sure that any has been created here on Earth (an implosion-squeeze is typically used, which is naturally followed very quickly by sample-destroying explosive expansion).

Well, that process, of trying to create metallic hydrogen, reminds me of a research effort known as "Inertial Confinement Fusion". The idea there is to squeeze the sample of hydrogen (a deuterium/tritium mixture) until it exceeds the kind of temperature and pressure found in the cores of stars, at which point a small nuclear fusion explosion occurs. So far they haven't been able to do this well enough to get more energy out of the explosion than they put into the squeeze, but they certainly haven't stopped trying (see link).

Are you thinking about "metallic deuterium" yet?

If Cold Fusion is true, and depends on conduction-band-electrons, then it logically follows that just about any size piece of pure metallic deuterium ought to explode nuclearly.

So let us construct a rocket engine based on that! In this rocket, the fuel tank contains tiny pellets of solid deuterium, each encased in a thin shell of solid hydrogen. These are "ordinary" frozen gases that I'm talking about here.

One pellet at a time is injected into the combustion chamber of the rocket engine. When the pellet reaches the appropriate spot, we will use an electric-discharge system to swat the pellet from multiple directions with blasts of electrons (not laser beams, see link).

When the overall/surrounding blast of electrons strikes the pellet, the outer shell is vaporized and explodes away, while the inner pellet is, per Action and Reaction, imploded significantly.

The key notion here is that we DON'T want an extreme blast. We only want to implode the pellet to the point where it becomes metallic deuterium. When that happens, a conduction-band is formed, full of bare deuterons, all of which are able to approach each other closely, thanks to the SECOND key fact:

Conduction-band electrons in a metal are "slow", while electrons in a hot plasma are "fast". Described in terms of the energy they contain, a slow electron is "very fuzzy", and Quantum Mechanics allows it to to be thought of as existing in a larger volume of space, compared to a high-energy/fast electron. It is precisely that fuzzy nature of slow electrons that the Cold Fusion hypothesis mentioned earlier uses, to explain how many electrons can get involved in-between two fusing deuterons. In a hot plasma the electrons are simply not fuzzy enough!

What I imagine happening in the squeezed pellet of metallic deuterium is that some initial Cold Fusions of the D+D->He4 variety will happen, and most of the electrons in the conduction band will as a result become too "hot" for them to become involved in other Cold Fusions. There may be an intermediate stage, however, before the electrons become too hot/energetic, in which the more-ordinary fusion reactions can occur, in which two deuteriums create Helium-3 or tritium, and a neutron or proton is released, along with gamma radiation. PERHAPS the energy released by these fusions will be enough to encourage the rest of the pellet to be involved; only experimentation can tell us for sure how much fusion will occur. If any, of course!!!

Here I am assuming that if the pellet is too big, we will simply be wasting both deuterium (larger portions of the pellet will fail to experience fusion), and energy (it takes more energy to squeeze a larger pellet), and so that's why I specified "tiny" pellets above.

The main advantage is that it takes a LOT less energy to squeeze a pellet of solid deuterium to the metallic-hydrogen point, than it does to squeeze it past the stellar-core point. "Breakeven", getting more energy out of the reaction than we put in, should be very possible!

Another possible advantage is that by using a blast of electrons to create the metallic hydrogen, when the metallic state forms it should include EXTRA electrons, added to it from the blast. The overall bit of metal, while it exists, will be very significantly negatively charged, and this means more electrons are present, to help catalyze Cold Fusions. This is specifically why I'm choosing electrons over lasers, in this Idea.

Note that since a lot of electromagnetic fields must exist surrounding the combustion chamber, to create the blast of electrons, it follows that those fields can be used to direct the hot plasma created by the fusioning/exploding pellet out the exhaust nozzle.

I tend to doubt that this engine will be powerful enough for direct lift-off from Earth, but it should work fine in outer space. Also, there is the radiation issue, because if an intermediate stage of fusions occurs, we don't want this rocket engine to be operating on Earth! We MIGHT consider containing the explosions and tapping their energy for power plants, but I think that pure Cold Fusion, free of radiation, is inherently superior for that purpose (see link).

Vernon, Sep 19 2007

About Metallic Hydrogen Metallic_20Hydrogen
As mentioned in the main text [Vernon, Sep 19 2007]

National Ignition Facility http://www.llnl.gov/nif/
The latest thing in Inertial Confinement Fusion, as mentioned in the main text. [Vernon, Sep 19 2007]

The Z Machine http://www.rdmag.co...0000000&PRODLETT=AN
Blasts of electrons used for Inertial Confinement Fusion experiments, as mentioned in the main text [Vernon, Sep 19 2007]

Cold Fusion Power Plant Large_20Scale_20Cold_20Fusion_20Reactor
As mentioned in the main text, should be radiation-free [Vernon, Sep 19 2007]

Water and Vacuum http://www.madsci.o...984359705.Ph.r.html
A detailed description of how water behaves when exposed to vacuum. As mentioned in an annotation. [Vernon, Sep 20 2007]

Cold Fusion Hypothesis http://www.nemitz.net/vernon/cfusion.txt
Updated; the works. [Vernon, Sep 23 2007]

Fusion rocket http://www.nasa.gov...fellows_slough.html
I read about E-Cat fusion also. [travbm, Nov 01 2015]


       I was half way through scrolling when I thought "This'll be Vernon or Treon". Then I noticed the capitalization and paragraph breaks, and figured it would be Vernon.
MaxwellBuchanan, Sep 19 2007

       If the pellet gets too hot for cold fusion to continue, maybe the explosion produced by pellet A could be used to compress pellet B and start the process there, avoiding multipke use of the elctron guns. You might want to limit the pellets available as this wouild be a chain reaction. Unless you were into that sort of thing thing.
bungston, Sep 19 2007

       If this works, how is the procedure to generate it different from any other attempt at inertial confinement fusion?   

       That is, wouldn't they already have seen this effect in the experiments already being performed?
GutPunchLullabies, Sep 20 2007

       [GutPunchLullibies], no, they would not have seen this effect, because even the first inertial-confinement experiments dumped far too much energy into the pellet. We need a solid-metallic state that is NOT so hot it that in the next instant it becomes a plasma, for this effect to be seen.
Vernon, Sep 20 2007

       If the level of power needed is so much lower, maybe something like sonic cavitation would be better?
GutPunchLullabies, Sep 20 2007

       [GutPunchLullibies], an electrical discharge system is plenty efficient (lots more efficient than lasers). We don't need anything so huge as the Z-Machine, to do the task described in the main text. Also, I'm wondering how you plan to do sonic cavitation in a liquid, when right next to it is the exhaust nozzle leading to the vacuum of outer space?
Vernon, Sep 20 2007

       I suppose I was guilty of ignoring the actual thrust of the idea. Probably I was thinking more about just trying to generate fusion at all than using it as thrust.   

       Still, perhaps a ball of water could float into the combustion chamber, with a tiny bubble of D2 inside. Cavitation is generated, right on the bubble- the water becomes reaction mass!
GutPunchLullabies, Sep 20 2007

       [GutPunchLullibies], you seem to be missing the fact that water doesn't stay water, when it is exposed to vacuum. Part of it instantly starts boiling, while the rest of it (maybe a 50/50 split) starts freezing. I added a link.
Vernon, Sep 20 2007

       I know my way around a rotary vacuum evaporator, thank you very much. But I wasn't envisioning the water bubble hanging around for any long period of time.
GutPunchLullabies, Sep 20 2007

       Bah. The heat of cold fusion is all due to the formation of hydrinos. Every pseudoscientist knows that.
ldischler, Sep 22 2007

       Ecat had something that could heat water maybe a cold fusion steam rocket?
travbm, Oct 29 2015

       Maxwell's demon steam rocket
Voice, Oct 29 2015

       Nasa was also working on a cold fusion engine.
travbm, Nov 01 2015


back: main index

business  computer  culture  fashion  food  halfbakery  home  other  product  public  science  sport  vehicle