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Fusion In Sonoluminescence (Again)?
srhuston writes "According to a story at the NY Times (first born child req'd, yadda yadda), 'Scientists are again claiming they have made a Sun in a jar, offering perhaps a revolutionary energy source, and this time even some skeptics find the evidence intriguing enough to call for a closer look.' This has been covered here before (First, second, third) but it looks like they claim that the latest round of experiments, using better detectors, 'offer more convincing data that the phenomenon is real'." The scientists involved come from Rensselaer Polytechnic Institute, Purdue University, Oak Ridge National Laboratory, and the Russian Academy of Science; here's their press release.
So, the problem with extracting energy from this is still sustainability combined with total output right? The amount of energy invested in the system will have to be exceeded by the energy produced or else it is for naught. The things about traditional plasma fusion is that energy output is extensive, but the reaction cannot be sustained. Bubble fusion appears to be sustainable, but likely does not produce significant caloric heat......
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Without understanding all the physics here, I think there may be something to this. One of the reasons chemists are kind of intrigued with sonochemistry (chemistry facilitated by sound) is that ultrasound generates "bubbles" (for lack of a better word) where the local temperatures can reach into the thousands of degrees of Celsius. You can do some really amazing chemical syntheses using ultrasound all because of the extremely high local temperatures generated. The same idea extends to using microwave ovens for chemistry. You can do lots of reactions in a microwave because of the intense and neatly condensed amount of heat generated.
So, there may really be something to this. It would be great if it did work out.
No trees were harmed in the composition of this; however, numerous electrons were inconvenienced.
I've done a bunch of work in sonoluminescence. It's deeply cool, don't get me wrong. But the highest temperature we were able to measure was about an order of magnitude too low for fusion. Even if our measuring had an error factor of two or three (not impossible, since we had to dope the water to get high enough brightness for using a spectrometer), I'm far from convinced.
I've had this sig for three days.
here's a link from a local paper.
An interesting quote from the article:"Willy Moss has been trying to reach that brass ring for a long time, and he's had way more money than Taleyarkhan and way more facilities," George said. "And when Taleyarkhan said he had neutrons, (Moss) sort of chimed in and said, 'No, no you don't,' because he was hard on the trail trying to get there first."
Seems there is a bit of anonymity here. In the defense of the researcher(s):The evidence now is "far more compelling," he said. "This time around, before publication took place, I deliberately involved a series of highly acclaimed physicists to come down to the lab and review the experimental setup and the way we were obtaining data and look at the experimental data."
After receiving positive reviews from them, he took the findings to the management of Oak Ridge, which conducted its own internal review, making the forthcoming publication "perhaps the most peer-reviewed paper in the history of the Oak Ridge National Laboratory," Taleyarkhan said.
if this particular discovery bears fruit, it might be really cool, as the cost for implementing it appears much lower than other attempted fusion experiments. But, how much would a true power plant cost? Or, how much would a "home unit" cost, since distributing the grid would probably be a better long-term solution to our power needs.
Then come the obvious questions about environmental impacts, as energy = heat, and here is an energy source without effective limits, hence limitless energy, and limitless heat. Perhaps they can use some of this limitless energy to pump the generated heat out of the planet? (ie, big heat radiators? Energy recycling? Something totally out of my depth?)
The cesspool just got a check and balance.
Our setup is presumably somewhat different than ours, but here's the summary of the five-minute do-it-your-self sonoluminescence kit:
Take a spherical flask, around 100ml or so. Bigger will mean lower frequencies but higher amplitudes needed. Fill the flask with water from the tap, up until the mensicus is just at the neck of the flask (that is, the water body is as close to spherical as possible). Attach on opposite sides of the flask two speakers, and somewhere else (we just put it between the two speakers, 90 degrees from each, but it doesn't really matter) a microphone.
Hook up a frequency generator to your speakers. Hook up your mic to a 'scope. You'll see the frequency being generated being picked up, slightly muffled and distorted, by the microphone. Tune your frequency until you get resonance; it'll be really, really obvious as the peaks of the mic output become much sharper than the input frequency. The actual frequency depends greatly on the water volume, and is very sensitive to temperature; for our particular setup 48kHz - 52kHz seems about right.
Turn off the light. Allow your eyes about 10 minutes to adjust. With this setup, you'll have light about as bright as a 5th-magnitude star. Any stray light at all will limit your detection. Slowly pump up the amplitude of your input. As the amplitude goes up, resonance frequency changes slightly, so tune as needed. The total amplitude needed is not very high, but it's probably going to be in the top half of a non-amplified signal generator's range.
The gas in the bubble, in this case, is a combination of (some) water vapor and (mostly) outgassed dissolved gasses. That's why we used tap water, above. Bottled water has much less dissolved gasses, so will be much dimmer. Also, water that sits there outgasses, so if you don't change your water it'll get dimmer over time. But we can exploit the fact that it's this added gas that glows, if we want.
Drill a very small hole (seven mil, for us) in the exact bottom of your glass flask. Attach a capilary of the same ID, or a bit more. Attach capilary to a gas canister, and input a low flow rate of gas while running the experiment as above. The idea is to have a near-constant flow of extremely small gas bubbles. If the bubbles are too big, nothing will happen at all; the temperature doesn't get high enough. If there are too many bubbles, you disturb resonance something awful. If the bubbles don't pass through the center, they'll be ignored. But if you get it just right, you'll get a nice burst of light (0th or 1st magnitude) when each bubble goes through, appearing as a constant point of light to the naked eye.
Argon works really nicely for this. Nitrogen works too. You don't want to use anything that dissolves too easily, because it will saturate the water; too much gas outgassing results in bubbles too big to glow. And you'll have to chance the water quite often, because everything will dissolve too much eventually (although helium seems to either dissolve less or just outgas from the top of the flask more quickly).
I presume what they're using in this experiment is hydrogen/deuterium gas, either fed in ordissolved in the water.
Since I should be studying for a midterm, I'll cut off my tutorial now, but feel free to ask more!
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When I was an undergrad at BYU, I had a friend who was working in this field. He worked under a mountain (less background radiation from cosmic rays). Made measurements while running, and compared to background when not running. Sadly, back then ('96 or '97) there was less radiation when running than when not (*very* disturbing). I told him he should change his project from "fusion generator" to "radiation absorber". Of course, the field has had 7-8 years to develop since then, so hopefully things are better now. Still, you have to wonder if it could scale up to a useful level....
I thought they were not using gas. I thought they were just using acetone who's hydrogen had been switched with deuterium... And ( from an earlier slashdot story on this ) wasn't the acetone used to minimise the amount of gas emitted into the bubbles so that the point they collaped onto was smaller and so more energy intense?
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Just one thing: the liquid is not water, but very cold duterated acetone - acetone with deuterium substituting for the hydrogen. By very cold: -20 to 0 degrees-F.
As cold acetone has a different density than water, you'll need to do some further playing with the driving frequency and amplitude.
Above comments come from having worked on the set up at Purdue about two years ago. Note then that my information is potentially two years out of date. Still, should get you started.
Also, on the topic of extracting usable energy: this is a real trick. The level of heat generated is very low. To most systems, it looks like waste heat. There are some heat engines that can take advantage of this, and there now exist "thermal diodes" that can effectively pipe low levels of heat. For more on this, get the NASA paper: NASA/CR-2003-212169 Advanced Energetics for Aeronautic Applications. Sorry, don't know of a link off hand.
- Jim Cavera
j_cavera@yahoo.com
Desktop fusion is no big deal, after all - the Farnsworth-Hirsch Fusor (
Here's a link ) does this.
The fusor operates by accelerating deuterons in a static electrical field towards a central locus ('juicy nugat center')(grin).
The trick to a fusor is that there's a lot of possible factors to setting one up:
among other factors. more info is at a homebrew club of amateur experimentors
I've been tempted to try this, but my wife has overruled all discussion of it. She has something against hot neutron sources in the house when we have 3 small kids. Alas. (Especially since this thing emits the particles in 3 dimensions, so shielding would be significant.)
SO: MY QUESTION FOR THE EXPERIMENTERS: WHAT IS THE TOTAL ENERGY (JOULES) PUT INTO THIS EXPERIMENT VS. HOW MUCH EMITTED? Is this going to be another wildly inefficient methodology, or does it have advantages over Fusor or Tocamak designs?
-- Kevin J. Rice
Unitarian Church: Freethinkers Congregate!
Now I am not a physicist or a chemist so this really exposes my ignorance but... what effects would doing this in a zero-g have? No need for a container to keep the spherical shape, this would aide in outgassing. Not sure how to supply the stream of bubbles, but if they could be introduced right to the center somehow, they would not move from there until they were 'ignited'.
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Yes, it could fly. And it did not need gas for flight as far as I know.
However, in the second movie, when Doc was struck by lighting, and sent back to 1885, the time circuits and flight circuits were fried, and the components to repair the time circuits were not going to be available until 1885. The time circuits being fried prevented the Doc from travling forward in time, so he stuck the Delorean in a cave and sent Marty a letter.
Back in 1955, they picked up the Delorean, repaired the time circuits, but NOT the flight circuits as they were beyond repair, and Marty went back to 1885 using the gasoline engine to get him up to 88mph. Marty however ripped the fuel line upon arriving in 1885. However, because the time circuits were undamaged, the situation wasn't the same as when the doc got sent back to 1885 by the lighting, so they were able to find an alternative way to accelerate the Delorean to get Marty back to 1985.
I wonder though... We've established that the Doc had no way of repairing the time circuits in 1885. And we have established that the Delorean needs 1.21 gigiawatts of electricity to travel forward in time. When the delorean was in 1885, this energy was provided by Mr. Fusion. Additionally, the time circuits were repaired in 1955, not 1885.
So how then, did doc manage to make NEW time circuits with only what was available in 1885 when he could not before, and how did he manage to generate 1.21 gigawatts of electricity with only a steam engine? A giant capacitor?
Basically, if you put a golf ball on top of a softball on top of a basketball and drop the 3-stack of balls onto the floor, then the golf ball will be sent upwards with dangerous force. A collapsing bubble seems similar to this, but I can't see right off how...
I wonder if you could make a gun by stacking 6 or seven ball bearings of decreasing size on top of each other so that when you hit the largest of them with a hammer the smallest would be fired like a bullet... Why couldn't you just use a cone shaped piece of metal with a weakly attached tip?
Eat at Joe's.
Several years ago I did quite a bit of work with Sonoluminsecence for my high school's science and engineering fair. Made it to the State science fair (anyone interested - the parent's tutorial is a great place to start).
The bit I'm particularly interested in is the stream of bubbles being supplied to the flask. When we did our setup, we just used tap water and let the bubble form spontaneously (or in some cases visibly drawn downwards from the water's surface). Getting argon or some other gas artificially introduced is a great idea. I would just wonder how difficult is it to align the stream of bubbles.
I'm a science nerd, but this idea is almost enough for me to dust off the old apparatus and try again with this innovation.
And people said the same thing about electricity. Sure, it's neet and it makes these bulb things glow, but how will it heat my house, cook my food, suck dirt from my rugs, chill my milk, etc...
Producing the energy is just the first step. If this does actually work you can bet your testicles that someone will figure out a way to harvest the energy.
Boobies never hurt anyone. - Sherry Glaser.
I went to BYU as a Physics major, and met Dr. Stephen Jones who was doing cold-fusion research at the same time Fleishman and Pons were doing theirs one hour north at the University of Utah. He said that the two teams found they were working independent of each other, and decided to hold a joint press conference to announce their findings. ANYWAY he said that the more accurate they got their neutron detectors, the less "cold fusion" they saw. Dr. Jones dropped "cold fusion", and experimented with sonoluminesce instead.
One of my friends (about eight years ago) decided to do his Senior project on this very topic (sonofusion) and was blessed with really acurate neutron detectors that he inherited from Dr. Jones. I asked him how the experiment was going, and he said very poorly. Whenever they turned the apparatus on it generated LESS neutrons than normal background noise! So I guess they were PREVENTING fusion!
Since it is a nitrogen fixating crop, nitrogen-based fertilizers would not be needed (such fertilizers are generally made from fossil fuel sources). Since hemp is naturally pest and disease resistant, herbacides and pesticides would not be needed (both of which are produced from oil). Used in rotation with other food crops (where possible to grow), use fertilizers, pesticides and herbacides for those crops would be reduced and/or eliminated.
The one great thing about bio-fuels over fossil fuels is that while both give off emmissions (though bio-fuels are typically lower), only bio-fuels close the carbon cycle (ie, carbon mono/dioxides) - whereas fossil fuels release the stored carbon back into the envioronment.
I tend to wonder if I will ever see hemp-based biofuel production in the US in my lifetime - I just recieved a letter back from one of my state reps about hemp and biofuel production, and I wasn't very impressed...
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I wonder if these results may lead to legitimacy for the claims of Grigg's hydrosonic pump -- a boiler-sized device that claims to generate over-unity heat generation from cavitation. The creator claims that it generates sonoluminescene which is its primary source of power.
Of course, as with any supposed "free energy" device, there's a lot of claims like, "Scientists have done tests that verify that it works," but I've never seen any published papers on the fact, and the device has been apparently known in the "free energy" fringe for over ten years, and supposedly there are buyers already using it to heat their water for much cheaper than usual.
(I keep meaning to look up this guy. He supposedly lives in my hometown.)
If it's for-profit but free, you're not the customer -- you're the product (e.g., the Slashdot Beta's "audience").
What the article is talking about is supplying enough energy to facilitate a reaction that could cause two hydrogen atoms to form a helium atom. When this occurs, the mass of the helium atom is slightly less than the sum of the two hydrogen masses. Since thermodynamics says the mass had to go somewhere, we account for the loss with an increase in energy (a la E=mc^2). The amount of energy released by this reaction is theoretically substantially greater than the energy used to force the two atoms together. At least, that's the gist of it.
Grammatical nitpick: the atoms don't get together, check their new weight against the required weight of their new self, and discard the rest through energy in accordance with the regulations from the heavenly bureau of thermodynamics.
Other than that, seems spot-on to me.
I dont know if i am noticing it more now or it is because Indians are actually doing better on the global stage. Rusi Taleyarkhan, the key player in this discovery/invention, obtained a bachelor's degree in mechanical engineering from the Indian Institute of Technology in 1977. He came to the United States shortly afterward for graduate studies at Rensselaer Polytechnic Institute, located in Troy, N.Y. In addition, he obtained a master's degree in nuclear science and engineering in 1978 and a doctorate in the same field in 1982. In all this talk about foreign workers coming to the USA, their contribution to American and Global knowledge is left unmentioned. This I think is tragic. In my view USA provides the best platform in the world for intelligent, creative and hardworking people and by doing that US benefits and stays ahead of the pack of nations. How I wish India could emulate US of A and make the smart people across the world work in India.
Deuterated acetone is fairly cheap (and less viscous than heavy water, so it is a good medium for cavitation). What would realy convince me would be repeating this experiments with partialy tritiated deuteroacetone. This would be hugely expensive (tritium is one of the most expensive common radionuclides) and unpleasant(because of the radioactivity of T). But D+T reaction has so much lower activation energy than D+D and it produces plenty of neutrons, so the detection should be so much easier, orders of magnitude above what they see right now.
(All common fission nukes and the fission parts of thermonuclear nukes are boosted with about half a gramm of T mixed in with D, to generate enough neutrons for complete fission of plutonium before the explosion spills it apart. Hiroshima non-boosted bomb had only 20% of theoretical yield. The infamous "Neutron bomb" is just a small boosted plutonium fission nuke, overboosted with excess T+D mix and without a reflector shield, so that excess of neutrons is produced and allowed to escape)
I doubt that we will ever figure out - and I suspect that even if we did figure out we couldn't do much about it