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Fusion Steam Boiler

Multiple Small Spherical Resonant-Cavities for a Sonoluminescent-Imploding-Microbubble-Fusion Steam Boiler
  [vote for,

:) Think of the Title of this as really being the above "Description".

Researchers have announced very recently, relative to this writing, that it is indeed possible to initiate tiny nuclear fusion explosions inside a deuterium-rich liquid. They weren't using heavy water, but herein I shall assume that it is possible to do this with heavy water.

The method employed involved a phenomenon known as "sonoluminescence", in which liquid suitably agitated by sound waves can generate small bubbles, which in turn (during the "low" amplitude section of a sound wave) can collapse violently enough to emit light. It was theorized that an enhanced version of this phenomenon might lead to nuclear fusion, and such has now been proved to be true.

They still need to pass the "breakeven" point, however (just like all those other fusion technologies), before this technique can become a practical energy source. I'm wasting no time offering some mad ideas related to that goal.

1) Since we ARE talking about microbubbles here, we do not need a large volume of liquid surrounding each microbubble. Herein I shall ask you to think in terms of grape-sized spheres, although even BB-size might be fine.

2) So, this overall steam boiler can be imagined as a nice cluster of small spheres, each one strong enough to withstand the pressures of many many fusion microexplosions. Also, we require small tubings to connect the spheres, so than an overall flow of liquid can be passed through this boiler.

3) We now digress to consider the phenomenon known as "resonance". Resonance is something that, under appropriate conditions, allows small inputs of energy to accumulate. For example, if you set yourself on a child's swing such that you are not touching the ground and are stationary, you can THEN "pump" your legs and body-position to begin swinging, and after a time, you can be swinging as widely as if someone had been pushing you. (I have DONE this, and perhaps most of you have too, but I have also sometimes wondered about problems with the Law of Conservation of Momentum here...but I concluded that a swingset constitutes a "system" comprised of swing AND support-strands, including some friction, and inside this system you can move your body's center of mass faster than the system can react to keep that center of mass in the same place. (Heh, maybe you are pushing air, and your motion is a reaction to THAT! Have to get an astronaut on a swing on the Moon, someday....) Anyway once you can acquire ANY overall motion, you can use the resonance effect to increase that motion.)

4) OK, so in the sonoluminescence phenomenon, we need a spherical sound-wave that passes through a central point. Thus we consider one of the specified small spheres, in which that sound wave can bounce off the spherical shell and head back toward that central point. Also, we want resonance to exist in this system, so that we can add tiny amounts of energy to the sound wave, and accumulate mighty compression effects at the center of the sphere. THIS is how we should be able to pass break-even, with respect to fusion energy -- and do so even with heavy water. I imagine numerous tiny piezoelectric transducers will be adequate for this task (several surrounding each small sphere).

5) It is interesting to note that the motion of sound waves through a liquid is somewhat independent of the overall motion of that liquid. Only a minor design adjustment of the small spherical cavity should allow for a small steady flow of fresh liquid through each sphere of our "grape cluster", while maintaining resonance of the sound waves inside each "grape".

6) Obviously, the smaller each "grape" in our cluster, the more grapes there can be within a given volume, and the more microfusion explosions per second there can be. This should be quite adequate to heat the liquid sufficiently so that it can be allowed to flash to steam (assuming grape cluster holds pressurized liquid, and we let it flow to an unpressurized region), or to create steam via an ordinary heat-exchanger. Then ordinary steam turbines can extract useful energy. You WILL be able to fit one of these in your car! And you might get 10,000km per liter of heavy water. :)

Vernon, Apr 19 2004

Bubble Fusion Replicated! http://www.scienced...03/040303080222.htm
Announcement. [Vernon, Oct 04 2004, last modified Oct 06 2004]

Sonoluminescence apparatus http://www.sonoluminescence.com/
Yes you can try this at home! [Vernon, Oct 04 2004, last modified Oct 06 2004]

The power of resonance. http://www.ketchum....bridgecollapse.html
"Galloping Gertie", the bridge that couldn't take it. [Vernon, Oct 04 2004, last modified Oct 06 2004]

Standard Resonant Cavities http://encyclopedia...m/resonant%20cavity
Some basic information, with links to more. [Vernon, Oct 04 2004, last modified Oct 06 2004]

Cerenkov Radiation http://dept.physics...nkov_radiation.html
Some advanced physics here. [Vernon, Oct 04 2004, last modified Oct 06 2004]

Cavitation http://cav2003.me.e.../Cav03-OS-3-003.pdf
Some reasonably detailed info, including pictures. [Vernon, Oct 04 2004, last modified Oct 06 2004]

Rogue Waves http://www.nswseaka.../47/roguewaves.html
Constructive interference is considered to be a significant cause. [Vernon, Oct 04 2004, last modified Oct 06 2004]

Constructive Interference http://scienceworld...veInterference.html
More info [Vernon, Oct 04 2004, last modified Oct 06 2004]

Krakatau http://www.indodige...ticle-print-16.html
A description of the eruption. [Vernon, Oct 04 2004, last modified Oct 06 2004]

Original article http://www.sciencem.../full/295/5561/1868
This has some more details about the choice of fluids and how they went about it. [bungston, Oct 04 2004, last modified Oct 06 2004]


       I can see how a spherical cell would help concentrating the sound waves, but I wonder why the second link specifies a *rectangular* cell?
mackerm, Apr 19 2004

       My guess is that the multiple transducers they use are each concave, like a parabolic dish, and so it doesn't matter what sort of chamber they use to hold the liquid. Remember that they are using the transducers alone to generate the microbubbles, while I am specifically looking to take advantage of the power of resonance.
Vernon, Apr 20 2004

       Isn’t there a problem with the build-up of fusion products in your spheres? For bubbles to collapse with any force, you can’t have any gasses in there, yet fusion is going to create helium (and free oxygen), which are going to build up in your containers, quickly dampening out any little bit of fusion.
ldischler, Apr 20 2004

       That's an awful lot of "if"s.   

       I wonder how much use resonance will be. How much sound energy would be left over after converting the water to steam?
phoenix, Apr 20 2004

       Very much, I like the idea. A hammer using to smash small bubbles I suggest. Thinking good is, using luminiscence locating bubbles for. My positive vote, you have this for.
finflazo, Apr 20 2004

       Ah...the white knight, I presume.
ldischler, Apr 20 2004

       Thank you Yoda.
yabba do yabba dabba, Apr 20 2004

       Regarding fusion byproducts in heavy water, about half are helium-3 and half are hydrogen-3 (the latter of which can be expected to recombine with the oxygen that is loosed when its hydrogen is fused). To some small extent helium can dissolve in water, and likely the more agitation that exists in the water, the more can be mixed in (even if only in the equivalent state of a "suspension" of tiny bubbles). The implication is that practically all the hydrogen-3 and at least some of the helium-3 will eventually find iself involved in secondary microbubble fusions, which is even more energetic than deuterium-deuterium fusions.   

       However, fusions involving hydrogen-3 or helium-3 will produce helium-4, which is non-fusible under these conditions, and must eventually be extracted and considered 'waste' (the most USEFUL waste in the world, considering future voracious need of liquid helium!). The easiset way to do this involves considering the flow of fluid through the boiler and heat exchanger (or turbine) and back to boiler -- there must be SOME place in that plumbing where we can allow gas to collect (including freed oxygen) that we can simply and occasionally bleed off with a valve (preferably to be collected for future use, as mentioned). Since no doubt a fair amount of helium-3 will also get out through that valve, no doubt we will want to save the released gas just so we can separate out the helium-3, and use it in other fusion reactors.   

       [phoenix], you seem to me misunderstanding something. The heavy water is not supposed to convert to steam (other than microbubble sized) inside the small spheres. I specifically mentioned connecting tubing to the spheres. This would obviously would allow us to let the heated water out of the spheres. THEN we can let it flash to steam (away from the sound waves confined to the resonance spheres), or we can take the radioactivity-controlling approach of using a heat exchanger.   

       (Folks, remember that we ARE talking nuclear power here, which always is associated with radioactivity. So, while this reactor might fit in a car, you might not actually want to own such a car.... A yacht, or a big truck that can carry sufficient shielding, is another vehicle altogether. Do note that some of that shielding can be more water, surrounding the entire "grape cluster" boiler....)
Vernon, Apr 20 2004

       "[phoenix], you seem to me misunderstanding something."
You can say that again. I must be missing the point of the "resonance chamber". Am I correct in thinking it both initiates and contains the fusion reaction? And the energy released by the reaction is supplemented and reused to initiate subsequent reactions? Where does all the energy go?

       I guess I don't understand how you expect to get more energy out of the system than goes in without a sustained fusion reaction.
phoenix, Apr 20 2004

       [aside: I can't really comment on the fusion, but the swing I have down pat. The system includes not only you and the swing, but the ground into which the swing is anchored. If you put the swing on roller-skates it would quite happily slide forwards and backwards showing that it does, indeed obey the law of conservation of momentum.]
st3f, Apr 20 2004

       /Also, we require small tubings/ - In this case, it would be small _hot_ tubing. I am a big fan of hot tubing, so you get my croissant.   

       The energy released would presumably be bled off as steam for a steam engine, or more likely used to heat a seperate steam apparatus since you would not want to waste your heavy water vapor.   

       I gather that the reason to use heavy water is that it is the deuterium-rich part that makes the fusion possible. I wonder why the bubble researchers did not used heavy water for their experiments?
bungston, Apr 20 2004

       [st3f], thanks! --BUT, will you sill be able to work yourself up to large swinging motion, in a swing that skated on ice? (My guess is that you could, if for no other reason than interaction with the air, as previously mentioned.)   

       [phoenix], There is no sustained fusion reaction here. Just many individual micro-explosions, surrounded by heavy water. I expect the water to absorb the heat, the expanding shell of steam to be damped out by the comparitively vastly cooler water. Sure, its temperature will go up some, but it won't immediately and completely turn to steam. This means each "grape" will still hold water for the next micro-explosion. AND because the "grape" has plumbing allowing fresh cooler water to replace the heated water, neither will a whole series of microfusions boil the water in the grape. I do understand that we want the FLOW of water through the small sphere to be slow enough that the water will come out near the boiling point (and if pressurized, then we want it near the boiling point of the pressurized water).   

       The point of the resonance chamber idea is that supposedly, as our resonant sound wave passes through the center of the sphere, it helps a microexplosion happen. And since the wave is moving at the pretty fast speed of sound in water, it will very quickly bounce off the insides of the sphere, and again pass through the center, to help another microexplosion. Meanwhile, to START and MAINTAIN this sound wave (assuming the explosions distort the waveform), we apply tiny tiny piezoelectric pulses at appropriate places and intervals. The main idea is that those tiny pulses build up, thanks to resonance, to the appropriate crescendo responsible for all those fusions -- and that is where the energy payoff comes from.   

       Note also that ideally we would want the size of the sphere to work WITH the expanding explosion-wave, to help cause the one of the next microexplosions. For example, consider our Initial Resonant Wave as being Wave A, while the Wave of Explosion is Wave B. I doubt that they will be naturally synchronized, BUT we have total control over the dimensions of the small sphere. We simply fix it so the "bounce time" for Wave A is such that when Wave B first happens, it happens exactly as Wave A has returned and WOULD have helped the next microexplosion. This particular explosion does not happen, since that initial explosion is still going on, but on the NEXT bounce, both Waves work together, meaning that we likely didn't have to apply any transducer energy at all (and perhaps could have EXTRACTED some energy, since piezoelectric crystals do work backwards! --Not to mention that I have just described a possible positive-feedback loop from which we had BETTER be able to extract energy!). Finally, note that I do understand that the result of such careful size-considerations might well mean we want BB-sized spheres, and not grape-sized spheres.   

       [bungston], I strongly suspect they chose a hydrocarbon because in terms of ratios of quantities of atoms, the percentage of hydrogen-to-carbon is greater than the percentage of hydrogen-to-oxygen in water. Obviously heating anything but hydrogen in a microbubble does not promote fusion, so hotter microbubbles will be needed for heavy water than for a deuterated hydrocarbon.
Vernon, Apr 20 2004

       Croissant for using 'piezoelectric' in your dialog.   

       I wonder if, anticipating gaps owed to the novelty of the science involved, experiments have yet determined characteristics of the hundreds of photons generated by this system's reactions.
dpsyplc, Apr 20 2004

       "[the sound energy] will very quickly bounce off the insides of the sphere, and again pass through the center, to help another microexplosion."
But that's my question. How much energy is left in the sound wave after it passes through the focal point of the "grape"? The energy going in surely stays there to create the bubble which will eventually collapse. Can there be much left over to resonate?

       Since the the collapse of the bubble causes the fusion reaction (and since you're not getting more energy out of the system than goes in) why not just use the energy required to run the piezoelectrics - to create the fusion reaction - to power your city/house/car?   

       That's what I'm taking away. Sorry if I'm missing something.
phoenix, Apr 20 2004

       [phoenix], pretend for a moment that NO fusion takes place in the liquid. In this circumstance the compression effect upon a microbubble is much like a spring; in accordance with Conservation of Energy, practically all the sound wave's effort that went into causing that compression...comes back out as the re-expansion of the compressed microbubble occurs. IF we manage to successfully reflect that sound-energy back toward the center of the sphere, then the only energy we need to add, to keep up a steady series of identical compressions and expansions, will be that needed to replace reflection-efficiency losses. --Well, I do also admit that SOME extra energy is going to be "lost" in the form of sonoluminescent photons, but how significant is that, really?   

       When fusion is included, that does NOT change the basic springing-phenomenon -- other than, perhaps, as already mentioned, the timimg of the expansion. And I can hardly believe you seem to expect fusion to add no energy at all to the re-expanding microbubble. Quote: "you're not getting more energy out of the system than goes in" --that is only true of CURRENT microbubble fusion experiments, which do not take advantage of any resonance-cavity effect. I stated quite-up-front, "I'm wasting no time offering some mad ideas related to that goal" (of passing break-even).   

       In more detail, I am suggesting that the tiny amount of energy we need to add, to replace reflectance and sonoluminescence losses, will turn out to be less than the energy yielded by fusion inside that compression-cycle's microbubble. We only pay an initial high price to START the sequence of microexplosions....   

       And so, I can only think that you are somehow assuming that a resonance effect cannot actually help the goal, but you have offered no data or reasoning why you make that assumption.
Vernon, Apr 21 2004

       toadinnov there might be a market for someone to produce vernon's ideas in an audio format...
engineer1, Apr 21 2004

       "When fusion is included, that does NOT change the basic springing-phenomenon -- other than, perhaps, as already mentioned, the timimg of the expansion."
Yes, but you're changing sound energy into...fusion and it's byproducts. How much usable sound is going to be left over after that process?

       "And I can hardly believe you seem to expect fusion to add no energy at all to the re-expanding microbubble."
Well, you've got me there. Why should I? I'd expect the fusion reaction to be completed long before the subsequent re-expansion.

       Bear in mind though that I've no education in this area which is why I'm asking these questions. I could be way off base, but all I see is a spring at the bottom of a piston and you telling me it makes the engine more efficient.
phoenix, Apr 21 2004

       [phoenix], No, sound energy is NOT being changed into fusion. It is simply being used to create a condition inside of which fusion can occur. That condition is simply extreme compression, and therefore will ALWAYS be spring-like in its ability to bounce back.   

       So, if one has to provide from scratch every time all the energy that goes into such a compression, then yes, so far the fusions that occur do not release enough energy to pay for that compression. (Note the generic-ness of the preceding statement, with respect to other forms of compression-to-fusion.) This is precisely why I want to invoke a resonance effect, so that we can effectively recycle the energy-of-compression, and thereby not need to pay for all of each compression from scratch.   

       Next, when a fusion microexplosion occurs, YES, the reaction is over-and-done-with practically instantly, and I do expect the force of that explosion to briefly exceed the speed of sound in the liquid (just like it is possible for particles to travel through an ordinary substance faster than the speed of light in that substance -- see "Cerenkov radiation" link). However, that explosion wave IS a kind of sound wave, and it will quickly become the equivalent of an ordinary sound wave, after it interacts with enough water. (Think about the volcanic explosion of Krakatau in 1883, which created a pressure wave in the atmosphere that was detected by barometers as it went around the world five times -- that pressure wave WAS ALSO a low-low-frequency sound wave.)   

       So, the main design problem here is that of trying to keep the initiating sound wave synchronized with the fusion explosion wave. I think it can be done, even if it requires fancy tricks like multiple initiating sound waves, such that a fast explosion wave passes the current sound wave, but by the time it slows down, it has actually joined and enhanced the prior sound wave, heh heh.
Vernon, Apr 21 2004

       You might consider using an ellipsoidal container. The sonic energy from an explosion at one focus would converge at the other, stimulating a second explosion, and so on, back and forth.
ldischler, Apr 21 2004

       [ldischler], True, and a nifty notion. (Doubters go to nearest toilet and spit, and watch the waves that form. If you spit in the right place -- one focal point -- you will see the expanding waves reconverge at the other focal point. This will work in three dimensions, with sound, just as well as it does in two, with surface-waves.) Still, remember that almost certainly the explosion wave will not stay synchronized with the sound wave that caused the compression that caused that explosion-wave...so even if we have two focal points for explosions, there will be two waves heading from one focus to the other. Consider what happens THEN: At that second focus, the first-arriving wave would cause a whole-new explosion-wave, that gets-ahead/out-of-sync with the wave that caused it...and the second-arriving wave causes a second explosion wave that gets-ahead (but at least this one catches-UP to the wave that had arrived first!). So now there are three waves heading back to the first focal point...   

       Thus it could be that a simple sphere may be best, with a deliberately matched pair of waves, such that every explosion caused by either wave always enhances the other (which, as mentioned in a prior annotation, constitutes a positive-feedback loop from which we had better be able to extract energy).
Vernon, Apr 21 2004

       What about another way of doing it?   

       Spin up the chamber containing the heavy water,and let gravity (centifugal) force the bubbles towards the sides of the chamber (and ultrasound push them back towards the centre (due to resonance) this would thus form a resonant 'ring of bubbles' when combeined with the ultrasound waves).   

       would this not pump up the stable bubble ring with ultrasound until the energy got to a critical fusion point?
Lunartick, Apr 21 2004

       [lunartick2], I have doubts about that. We are not talking about persistant bubbles here. Please check out the "shrimp" link provided by [q2cannonfodder], and the descriptions of bubbles relating to "cavitation". In a way, the physical motion of matter through water, that causes cavitation, is being emulated by sound waves here, to create those sonoluminescent bubbles. Likely they are caused by "constructive interference" that temporarily dumps enough energy into a tiny volume of water to boil it to become a bubble of steam. They collapse as the waves that combined to form them continue on their way (they are surrounded by much colder liquid, after all!)
Vernon, Apr 21 2004

       "No, sound energy is NOT being changed into fusion. It is simply being used to create a condition inside of which fusion can occur."
Um, okay. Sort of in the same way a spark plug doesn't cause the piston to move, it only creates the condition wherein combustion can occur. But no one expects to have the spark (re)cycle through the electrical system, get a slight boost from the battery and start the next combustion cycle. I fail to see how the energy isn't consumed.

       The process (as I understand it) goes:
Sound wave -> Bubble expansion
Bubble expansion -> Bubble collapse
Bubble collapses -> Fusion Reaction
Sound wave -> Fusion Reaction
(I understand heavy water and neutrons are part of the process as well, but they're fuel, not spark)

       Again, if I'm misunderstanding or missing something, I apologize. I'm not trying to be argumentative, just trying to rationalize. I won't mention my reservations again.
phoenix, Apr 21 2004

       [phoenix], in a spark-driven engine, the energy of the spark partly goes into aiding the motion of the piston (a trivial contribution), partly heats the water jacket surrounding the engine (again trivial), and partly goes out the exhaust pipe (again trivial). The energy of te spark is vastly less than the energy released by chemical combustion of the fuel/air mix. And, remember that such engines DO use the power they produce to, among other things, create more sparks! (You CAN think of this as recycling the spark, but conversion-efficiency losses, from one form of energy to another, mean that future sparks are basically "paid for" by the combustion process.)   

       In attempting fusion, we must put a great deal of energy into a "spark", as you know. UNLIKE an ordinary spark, however, the opportunity presented to us by the phenomenon of sonoluminescence is that we can use a form of energy (sound waves) that need not quickly degrade to random heat. A resonance cavity is a place where a waveform can persist with very little degradation. This is the key to becoming able to that which is not really possible in an ordinary engine: to directly recycle the energy of the "spark". (Actually, the energy simply persists as a sound wave, and all we do is control the way it bounces!)   

       With respect to consumption of energy of our sound-wave/spark, I tried to explain before that the phenomenon of compression is a thing that mostly Conserves energy. Now, obviously if some of the compressed water RESPONDS by turning to steam, then this does count as some extraction of energy from the sound wave. However, when that steam-bubble collapses, it becomes the source of another sound-wave! (see shrimp link). This is GREAT, in that very little of the original sound wave will actually be converted to random heat.   

       Again, as I've mentioned before, even in the absence of fusion, we want to try to get that second sound wave to become synchronized with **A** primary/spark-initiating sound-wave -- and so I mentioned that multiple initiators may be the way to go -- because THAT means we will truly be recycling our sound-energy.
Vernon, Apr 21 2004

       I linked the bubble fusion group's paper from 2002. It has more specifics about their apparatus and choice of fluids.   

       I have been thinking about this idea more. I like it more. Sound energy can be recaptured in a way that other types of energy cannot. Although I suspect [phoenix] is right, and a fair amount of energy is lost to heat and light in these infernal bubbles.
bungston, Apr 22 2004

       <on a completely different track>: If the bubbles could be created and destroyed accurately in 3D space, then a 3D display would be possible. But only one colour. Ultrasonic TV!
Ling, Apr 23 2004


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