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Fusion Using Sonic Compression 95

Posted by michael from the wave-theory dept.
The Only Druid writes "Scientists have confirmed the use of sonic waves to create the necessary compression in plasma to achieve nuclear fusion, far more effectively and cheaply than any other method. Val Kilmer was unavailable for comment."
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Fusion Using Sonic Compression More

Fusion Using Sonic Compression

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  • Keep your shirts on (Score:3, Informative)

    by Lonesome Squash ( 676652 ) on Thursday January 20, 2005 @10:32AM (#11419786)
    TFA (a press release about the pending publication) is woefully short of the kind of info we want to see. It appears to be a nice confirmation of earlier claims of cavitation-induced fusion that were disputed due to imprecise measuring technique. I couldn't find anything about it on Phys Rev E [aps.org] yet.

    In any event, it's not Mr. Fusion. The amount of actual fusion is tiny, and well below any commercially or societally interesting level.

    • It's also from March 2, 2004. Looks like a repost from fark to me.
    • I couldn't find anything about it on Phys Rev E yet.

      Yeah, well Bob Park shat all over it [aps.org] when the experiment was first reported, as he's want to do for anything not involving big-budget tokamaks.

      There's a difference between being professionally skeptical and being openly hostile towards unexpected developments in science. I'm afraid APS/Park fall on the side of being high-priests of high-energy. A scientist must be both completely open minded and rigorously skeptical - those two qualities are not exclu
  • This article is dated March, 2004. Hope that provides some context as the mentioned article should allready be published. Further, I imagine there has been more recent research into the field in the last year.
  • I can't find in the article whether or not it released more energy than they used to start the fusion. I've heard this has always been a problem so far with using fusion practically.

    • Re:Did it release more energy than it absorbed? (Score:4, Interesting)

      by j_cavera ( 758777 ) on Thursday January 20, 2005 @10:44AM (#11419926)
      Worked on this project for a bit. Yes, it does release more energy that it takes to start -- in theory. In the lab, you need about 100 watts of power to get a few milliwatts of heat. Bear in mind that this technology is in its infancy and may scale upward to the net-gain level. BUT due to temperature constraints in the apparatus (it likes cold), it will be difficult to get this up to power-generation level.

      - Jim
    • Adding heat to a lukewarm bath of deuterated acetone is one thing. Even making bubbles in a truly hot fluid (such as water in a high-pressure boiler) is quite another. The bubble phenomenon appears to depend on there being a large enthalpy and density difference between the liquid and vapor phases; as you get toward the critical temperature and pressure, this difference decreases until it finally disappears. Supercritical = no more bubbles.

      High temperatures are important. You can't run an efficient heat en

      • Re:And can it release it usefully? (Score:4, Insightful)

        by WhiplashII ( 542766 ) on Thursday January 20, 2005 @12:37PM (#11421367) Homepage Journal
        What you say is true, but less true is deep space. Out beyond Jupiter or so, there is very little energy available. Everything is very low temperature, and radiation cooling very quickly gets you to extremely cold temperatures (40 K is reasonable, as I remember).

        Something like this could work as a Mr. Fusion for deep space probes - it sounds like a perfect match. Deep Space probes typically don't even need that much power!

        • Running a heat engine with a very cold sink temperature begs the question: what do you do for a radiator? Blackbody radiation scales as the fourth power of absolute temperature; cutting your radiator temperature from 300 K to 150 K multiplies the required size of your radiator by sixteen. The size of the heat engine goes up too, but not quite so badly. Eventually your probe's power supply takes over.

          There comes a time to forget the nuclear phobia and go with plutonium RTG's or even a small fission reactor.

          • Well, yes - but you could go further with this than an RTG (For the same mass, more energy available). It is true that the low temperatures would limit energy output, but one problem is keeping the spacecraft warm (well, near freezing actually). This could help with that, and provide a few watts of power. The radiator would be the spacecraft itself. Even at the fourth power, your spacecraft will be radiating on the order of 100 watts at 250-300 K. (Your example of 150 K is rather extreme - at that temp

            • ... you could go further with this than an RTG (For the same mass, more energy available).

              Really? Consider total mission mass. A reactor or RTG can run its heat source at a fairly high temperature, and the power conversion hardware and radiators are not very large. A low-temperature heat source would require a very large and heavy radiator; unless you have a very long mission, the RTG and reactor can beat it by just adding more fuel.

              The radiator would be the spacecraft itself.

              Now you've added a requi

              • The total mass issue is a problem only for small spacecraft (basically you are assuming that fuel is a low proportion of mass, I am assuming a high proportion). We are both right for different assumptions.

                As for Carnot efficiency and such, I kept my post rather vague on that point intentionally. There are devices that achieve near carnot efficiency, and such devices tend to be low power as well. In your example you mention a steam generator - I think we both agree that it is unlikely that a steam gener

                • top of the line steam power plants are near 70% efficient

                  Bull. Show me one. (Combined cycle hits about 60%, but that's not a pure steam cycle.)

                  nuclear fuel tends not to last too well. Typically years, not decades.

                  Every bit of nuclear fuel we have has been hanging around since the formation of the Earth, 4.3 billion years ago. True, Pu-238 isn't good for more than about 50 years (half-life ~90 years) but we make it and we only use it because our primary missions only run about 10 years.

                  If the nuclear

                  • Bull. Show me one...

                    The particular one I had in mind was in a physical document, not online. Remember, that for space use you will spend enough to use top of the line parts no matter what method you choose. Online, the best I could find was in this link:

                    http://www.naturalgas.org/overview/uses_eletrical . asp [naturalgas.org]

                    It has a micro-turbine generator available that is 80% efficient. (I don't know where that came from, the highest I had ever heard of was 70%)

                    As for the rest, we have never made any near a ce
                    • If you look closely at that page, you'll notice that the picture of that unit is from Capstone Turbine [capstoneturbine.com]. The electric conversion efficiency of Capstone units is about 28% peak [capstoneturbine.com] (see graph on page 3). They can claim 80% energy recovered, but that includes the heat captured as well as the electricity generated.

                      (1)

                      we have never made any near a century life atomic batteries, and (2) we have never tried to make a generator from this technology.

                      You're comparing cherries and watermelons.

                      1. We've made dozens of atom
                    • That is pretty much exactly what I was saying, but obviously not what I was communicating.

                      My only caviot is that while an RTG would probably be a good bet, current designs would not acheive the lifetime I was talking about - and simply adding more material doesn't help that much. After sitting around for decades, radioactive material must be reprocessed (as in repurified) before it can be used in the same reactor. As I said, any sane person would not bet on this technology yet - but people were discount
                    • Incidentally, the efficiency number claimed by Capstone is based on the lower heating value (LHV) of the fuel, not the higher heating value (HHV) which includes the heat of vaporization of the water. Thus, the energy input is understated and the efficiency is overstated.

                      After sitting around for decades, radioactive material must be reprocessed (as in repurified) before it can be used in the same reactor.

                      That's not true, and betrays a misconception. Reprocessing is required to remove fission products, whi

                    • Right, it is confusing to talk about both RTGs and standard reactors. I was talking about RTGs, because they would be mass competitive - a nuclear reactor would not have this problem but would weigh a lot.

                      And, of course, what if you have a melt down (up?) in space? You might make it radioactive! ;-}

                  • Oh, and I notice that for some reason you do not include combined cycle plants? OK, if you throw out half the energy, then yes it would not be that efficient.

                    My recommendation: Do not throw out half the energy.

                    • Did you fail to notice the emphasis on the difference between the Carnot efficiency and the actual efficiency? Change the test case and the numbers also change. Heck, look up the combustion temperature of the UHT turbines used in combined-cycle plants and calculate the Carnot efficiency for that case yourself. Is 60% good or bad?
                    • Um, nothing can do better than carnot efficiency, even with cogeneration... unless you are talking about heating water as useful energy or something.

                      Cogeneration can mean that, but it normally (well, for some values of normally) means that the waste heat from one carnot based cycle is used on another one.

                    • nothing can do better than carnot efficiency

                      Thanks for evading the question. Is 60% good or bad for that particular high-side temperature? Is it a large (good) or small (bad) fraction of the theoretical maximum?

                      Cogeneration can mean that, but it normally (well, for some values of normally) means that the waste heat from one carnot based cycle is used on another one.

                      You've just proven that you do not understand "Carnot cycle". Go take a course in thermodynamics and clear some of those misconceptions o

                    • Wow, you sure are abrasive...

                      You can get within 90% of carnot efficiency with Stirling engines. Steam engines probably approach 80%, but I have no data to calculate that.

                      The quintessential example of the multiple cycle is a stirling engine (or thermoelectric pile) running on the exhaust of a turbine. Turbines are not efficient at getting the low temperature (under 200 C, say) energy out. No one uses a true carnot cycle, but most people do talk about heat engines as carnot engines. I suppose it is te
                    • You can expect people to be abrasive or dismissive when you presume to lecture them on things that they've studied in depth and you have no clue about. Example:

                      Steam engines probably approach 80%, but I have no data to calculate that.

                      And you said this shortly after I gave you proof that the typical figure is closer to 50%. The turbines can recover 80% or more of the available energy in the steam, but the availability is nowhere near 80% of the heat input.

                      I suspect that you have no clue about the meanin

                    • Please read what I said. I was talking about available energy. To quote "80% of carnot..."

                      By the way, your actions label you as a dork. Thats why I get paid 10X what you do, because I can discuss things with people that have less knowlege than myself without making them feel stupid. If I have less knowlege than you on Thermodynamics (hey, it is possible), then try to educate me. Don't try to show me how much smarter you are than me.

                      However, I believe what is really going on is that we have both st
      • It's not just a matter of creating the bubbles. By adding enough ultrasonic energy of the proper frequency, one can create bubbles in anything. The thing is that the bubbles have to collapse with a particular velocity. This is dependant on the temperature of the fluid. And, unfortunately, colder is better in this case. Yes, thermodynamic efficiency requires high temperatures. Yes, there are ways of extracting useful energy from small temperature differences (rubber-band heat engines, thermocouples, et

  • ITER (Score:1)

    by myukew ( 823565 )
    Does this make the bazillions we paid for ITER (http://www.iter.org/ [iter.org]) useless?
    • Not at all. Without those bazillions, all those physics geeks would have been stuck living in the basement and leeching off their parents during their post-docs. I'd say that buying boxters for nerds is anything but useless. (Vrrooom, vrroom!)
  • what does Keaneau Reeves have to say about this?
    • "The Only Druid writes "Scientists have confirmed the use of sonic waves to create the necessary compression in plasma to achieve nuclear fusion, far more effectively and cheaply than any other method. Val Kilmer was unavailable for comment."
      • Uhm, V.K. was just some clueless spy guy...you really need to talk to Elizabeth Shue. On second though, I'll go talk to her and relate to slashdot what she had to say.

        no! no! I'm not stalking anyone! I'm trying to get a comment from Elizabeth Shue, for slashdot a big online news website, on the recent use of senic waves to create compression in plasma for the purpose of starting a nuclear fission reaction. What? you never heard of slashdot? of nuclear fission? plasma? No, I'm not talking about a televisio

  • "You don't believe in any of this cold fusion mumbo jumbo, do you?"

    I loved that movie. Mindless, flashy fun. That, and Elizabeth Shue is teh hottie

  • While this is a good piece of science, by itself it is not a step towards anything economically useable as they had to do a lot of work just to verify that there was energy released. In a viable fusion reactor this should not be difficult to prove. This might one day lead to something, but there is no obvious application at this point.
    • However, we have pleanty of excess sonic vibrations to use with this method...this season of American Idol demonstrated that...
    • That is such a moronic response! (Sorry, I really get sick of hearing things like that!)

      What you mean is that you cannot think of an application. I can think of several, some of which would probably work almost as is. For example, it could be used to heat interstellar probes above 4 K - you have to take all your energy with you because interstellar space has no energy sources available. It works best in the cold - perfect for some applications.

      Please, please do not assume that there are no applicati
    • No? If this experimental results can indeed be confirmed this can very well be the next clean energy source. This experiment can basically be done with a table-top setup, so plenty of research facilities will hop on the train and try to extend the technology. Standing ultrasonic waves are nothing extraordinary.
      Other possible fusion reactors like ITER are huge plants which cost billions of euros and require an extensive amount of collaboration of many nations to build. Same goes for lasers, high-energy lase
  • Its old news that its possible to use soundwaves to create extremely high temperatures, however controlling it has been very hard, i first read about this about 10 years ago. You need a bubble that is almost a perfect sphere via evaporation and then apply the sound waves, this causes the material to implode very aggressively. Its great to se a promising method have developed further, because the JET project (Joint European Torus) is not new at all, and with a proper "spark plug" hot fusion seems to be close

  • Not cold fusion! (Score:1, Interesting)

    by Handbrewer ( 817519 )
    Please people, this is not for cold fusion use - its for starting a hot fusion process. That needs millions of degrees celcius, high material density and so forth. This is one promising solution for the hot fusion "spark plug". http://www.jet.efda.org/ [efda.org]
    The key to hot fusion is material density and temperature, containing the plasma is extremely hard.
    • Are you sure about that? I thought the difference between cold fusion and hot fusion was that hot fusion is started by a nuclear fission reaction? It doesn't have to do with the temperature of the reaction, it is just that the only way we have had of creating fusion is to use a fission bomb to compress and heat the fusable material.

      So to me this sounds like a step towards cold fusion because you are using sound to compress the material, not fission. I think the 'hot' refers to radioactivity.

      • I thought the difference between cold fusion and hot fusion was that hot fusion is started by a nuclear fission reaction?

        You're thinking of the H-bomb, whereby a nuclear fission bomb is the trigger for the fusion reaction (just like a conventional high explosive is used to implode the fissionable core to supercritical mass.)

        ITER, for instance, and other torus reactors involve no fission whatsoever...there is no uranium or plutonium used. They operate by magnetic confinement of the plasma which is heated


    • I couldn't agree more - this isn't cold fusion, it's hot 'nano-fusion'. Let's start using the new name and see if it catches on.

    • Well, the term "cold fusion", if taken literally, can never be applied to any form of fusion we have imagined. On an atomic scale, the energy of a single atom is its "heat", and the 1 Mev or so required is extremely hot!

      Personally, I think it is fair to call anything that has an average chamber temperature below 100 C "cold fusion", because it is cold enough to make apparatus design safe and easy.

      Remember, cold is a relative term. Compared to a standard fusion reactor, the center of the sun is "cold".
      • Umm... considering that the center is where the fusion is occuring and that is a result of the crushing weight of 98% of the solar system, I would hazard a guess that a fusion reactor core has similar temperatures to the center of the sun.
        • That's what is funny - it really isn't. Thermonuclear weapons are a lot hotter than the center of the sun - the sun is just under more pressure. The amount of fusion is related to temperature times pressure, so you can have either one. The sun uses pressure more, our bombs use temperature more. (At least as far as I can tell. No insider info here...)

          So in comparison to the only efficient fusion reactor we have (somebody sent us up the bomb), the natural reactors (stars) ARE cold fusion!

  • Val Kilmer? (Score:3)

    by Kosi ( 589267 ) on Thursday January 20, 2005 @10:53AM (#11420027)
    What has he got to do with physics?

    • Re:Val Kilmer? (Score:3, Informative)

      by bhima ( 46039 )
      It's a reference to a movie he was in: "The Saint".

    • The Saint (Score:3, Informative)

      by roseblood ( 631824 )
      http://www.imdb.com/title/tt0120053/

      As a young orphan, a boy[Val Kilmer] refuses to accept the name given him by priests and instead chooses to take on the name of Simon Templar after the Saint of magic. Speed ahead and the young boy is now a master thief in bidding wars with countries for his services. Using his skills of master disguise, he eludes all pursuers as he assumes names associated with the various Saints. In this role after stealing from a Russian industrialist, the industrialist hires The Sain
  • ...but could someone explain the Val Kilmer reference? I have a feeling there's a funny I'm missing. =)
    • Simon Templar[Val Kilmer] - a fictitious name a young orphan boy invented for himself in a Hong Kong orphanage years ago - is now a suave, debonair, international thief who needs to pull-off just one more exuberant heist to put him at the $50 million mark in his Swiss bank account (his goal amount for retirement). An easy job: simply steal Dr. Emma Russel's formula for cold-fusion, and deliver it to a Russian billionaire bent on sending Russia back to Communism - no problem, Right? Wrong! There's one thing
    • It's not very funny. Val Kilmer and Elisabeth Shue were in The Saint http://imdb.com/title/tt0120053/plotsummary [imdb.com], where the lovely Elisabeth plays a physicist who develops a formula for cold fusion using something similar to what TFA is talking about (although TFA is talking about "hot" fusion, not Pons/Fleischmann cold fusion.)

      Its a cheesy thriller movie, very little science, just 2 good looking actors getting it on. Worth a Friday night though.
  • The Val Kilmer reference is from this movie [imdb.com].
  • Here's my naive idea for fusion confinement. How about a giant container filled with some liquid. And this container is spinning in such a way that a bubble of hydrogen/helium whatever fuel is kept in the center. Could you then initiate fusion in the bubble and rely on the liquid around it to contain it?

  • ... you know, the movie where he outruns the shock wave on a motorcycle?

    Val Kilmer built a giant death-ray laser.
    • That was the movie "Chain Reaction" [yahoo.com]. I'm not sure the phrase "cold fusion" was used in that movie, but I did get the impression that something like that was what it was about.
      • It's been a long time and God knows it was primarily memorable for things like the supersonic motorcycle, but I *think* they actually used the sonoluminescence hack as the explanation for making the fusion work.

        • Re:You mean Keanu Reeves (Score:1, Funny)

          by Anonymous Coward
          Yes, the acoustic energy needed to cause sonoluminesence came from a Wyld Stallyns concert. San Dimas High School Nuclear Fusion ROCKS!

          Seriously, though, yeah, you're right about the sonoluminescence thing.

      • Chain reaction made it *very* clear that the energy came from burning hydrogen--they demonstrate it with a match! Basically they built a perpetual motion machine--electrolyze the water into hydrogen and oxygen, burn the hydrogen (combining it with oxygen) to get water, lather rinse repeat.

  • I think you mean... (Score:3, Informative)

    by centauri ( 217890 ) on Thursday January 20, 2005 @11:31AM (#11420517) Homepage
    Keanu Reeves [imdb.com].
    • Nope, they mean Val Kilmer [imdb.com].
    • Nah, Val Kilmer [imdb.com] was indeed what he meant.
    • The plot vehicle in that movie wasn't fusion, it was cheap efficient hydrogen production. Of course, I can understand why you would be confused, the movie consisted of 1% science fiction and 99% running, shooting and "whoa"ing.
      • Holy crap, you're right! And all this time I thought it was fusion too. Now I'm really confused as to the source of that humongous explosion... I guess if a tank of water can emit enough hydrogen, all you need to do then is add the burning shell of a zeppelin and BOOM!
        • Well there was a laser involved. You know it's gunna explode if there's a laser involved. If the rest of that movie had been as interesting as the first 5 minutes it might have been a cult classic with geeks. Now there's a movie that would be worth watching: physics genius invents ground breaking technology, world is transformed as a result. Of course, you'd need some freakin' master of a director to make it even remotely interesting.

  • published (Score:1, Informative)

    by Anonymous Coward
    The paper was published: Taleyarkhan, R. P. et al. 2004, Phys. Rev. E, 69, 036109, with an erratum this month (2005) Phys. Rev. E, 71, 019901.
  • This last year's news.
  • Did anyone notice this on the top of the page?

    FOR RELEASE: IMMEDIATE
    March 2, 2004

    Why wasn't this posted 10 months ago? More importantly, why is it being posted now?
  • There was an article on Slashdot [slashdot.org] almost a year ago pointing to this exact same press release (dated March 2, 2004).
  • Chain Reaction is much more replated to this story...

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