Posted on 03/07/2002 1:31:06 AM PST by The Raven
OAK RIDGE - Rusi Taleyarkhan is 49 years old, suddenly famous and emotionally spent.
"It's been a pressure-cooker for the past one year," said the senior scientist at Oak Ridge National Laboratory who has attracted worldwide attention this week regarding his research on "bubble fusion."
In January 2001, after four years of study and experimentation, Taleyarkhan started seeing "interesting results" in his research with sono-luminescence - a phenomenon in which sound waves produce bubbles that collapse explosively and release energy in the form of light flashes. The feedback gave him confidence that the tabletop experiment might achieve nuclear fusion - the fusing of deuterium atoms at high temperatures.
"I've been living on adrenaline since then," he said.
On Monday, however, the stress became too much. On the same day that Science magazine unexpectedly lifted an embargo on its March 8 publication and broadly released a paper revealing the preliminary - and controversial -results of his research effort, Taleyarkhan was in bed. The long-standing intensity had made him sick.
"I couldn't get off my back," he said.
When he returned to work Tuesday morning, a couple of hundred e-mails and a bank full of phone messages awaited him. Colleagues from around the world -including friends in his native India -offered congratulations. Others wanted more details on technique and analysis. Reporters posed the obvious questions, most notably, "Is this 'cold fusion' all over again?"
Taleyarkhan said his favorite message was from a one-time skeptic, a fellow scientist who previously had doubted his research in the strongest terms. The message simply congratulated the researcher on his perseverance.
Having the work published was a huge relief. For months the results had been pored over in the peer-review process, every detail challenged by experts inside ORNL and a dozen others retained by Science magazine -one of the world's premier scientific journals. Taleyarkhan and his research team members addressed the questions one-by-one.
One senior-level administrator in Oak Ridge told Taleyarkhan he had never seen a scientific paper receive such critical attention or so many reviews.
Why? Mostly because of the unfortunate history of tabletop fusion experiments, especially the 1989 fiasco known as "cold fusion."
In that instance, Martin Fleishmann and Stanley Pons of the University of Utah announced prematurely that they had achieved a fusion reaction at room temperature through chemical means and thus set off wild speculation about the possibilities. The celebrated work had not undergone peer review and when scientists around the globe failed to reproduce their results, the affair turned into one giant embarrassment for the Utah professors and science in general.
Taleyarkhan's research was based on different principles and was decidedly not cold fusion, but there were enough similarities that it would draw the inevitable comparisons. Taleyarkhan knew it would. ORNL management knew it. Science magazine knew it, too.
Everybody knew there'd be plenty of hoopla surrounding the work because once again scientists were claiming to have achieved nuclear fusion in a beaker. Or at least there was evidence that appeared to support such a claim, including the presence of radioactive tritium and the timely release of neutrons from the experimental chamber.
In a visit to his laboratory Wednesday, Taleyarkhan showed the News-Sentinel his equipment. He said he has performed the bubble experiment more than 100 times there, each time taking apart and reassembling the test apparatus.
The experiments rely on what's called "acoustic cavitation," which is the collapse of bubbles formed during the process using sound waves.
According to information from ORNL, cavitation works like this: "When a sound wave propagates through a liquid, the molecules in the liquid are subjected to positive and negative pressures. During the negative pressure phase of the wave, tiny bubbles in the liquid can grow dramatically (up to a factor of 1,000 in volume), since the pressure is below the vapor pressure. When the positive pressure of the sound wave passes, the bubble collapses, and the energy accumulated in the bubble during growth is released."
Taleyarkhan did a couple of things to enhance the research environment. He used acetone, an organic liquid known best to many as nail-polish remover, because it allowed researchers to achieve a high tensile state in the liquid without bubbles collapsing too quickly - a problem known as premature cavitation. Deuterium also was added, thus allowing scientists to study the possible nuclear reaction of deuterium atoms fusing.
The process then was stimulated with strong pulses of neutrons.
The research team reportedly produced bubbles 1,000 times bigger than any achieved by prior studies, with resulting clouds of bubbles interacting and grandly multiplying the implosive force as they collapsed.
Taleyarkhan estimates that the collapsing bubbles generated temperatures approaching 18 million degrees Fahrenheit in pockets of the deuterated acetone - enough to allow the fusion process to take place.
Doesn't that melt everything in sight?
"The bulk of the fluid remains at room-temperature conditions," the scientist said. "You're nucleating certain regions, which form vapor to grow up to astronomical size in proportion to their original size. (The biggest bubbles reach the size of a pencil-top eraser.) And then they implode. It's the implosion phase that is intense compression and intense temperature rises and flashes of light at that point. So it is only those individual regions at any given point in time that are experiencing those extreme temperatures and those extreme states. That's the beauty of this system."
About the only protection required for researchers is a stack of paraffin bricks to absorb the neutrons coming off the cylindrical beaker. The glass beaker is about the height of three coffee cups.
Now that his work has been published, he has two goals:
Attempt to "scale up" the experiment to evaluate the bubble technique's potential as an energy source. Although ORNL management has downplayed the feasibility of building a bubble chamber big enough to use this fusion process as a power producer, Taleyarkhan said he's cautiously optimistic.
"We seem to have a fighting chance," he said. "But not having done it, there are no promises to be made."
- Work with researchers around the world to help replicate the experiments.
"It's so important that we get credibility from folks other than Oak Ridge and other than the people we collaborated with," Taleyarkhan said.
He said he is confident the work will hold up under scrutiny. Much attention already has been given to the fact that two other Oak Ridge physicists, Dan Shapira and Michael Saltmarsh, attempted to replicate the experiment and did not find the anticipated level of neutrons coming from the process that would indicate fusion taking place.
Taleyarkhan said he has reviewed the work of Shapira and Saltmarsh and believes their data actually support his results, that it was an issue of misinterpretation.
Top ORNL officials have remained neutral on the neutron issue, saying future experiments will verify the true results.
Taleyarkhan came to Oak Ridge National Laboratory 14 years ago after doing advanced fuel designs for Westinghouse Electric Co. in Pittsburgh.
He grew up in a small village called Dohad in western India not far from Bombay. He received his bachelor's degree in engineering at the Indian Institute of Technology. He received a doctorate in nuclear science and engineering at Rensselaer Polytechnic Institute in New York.
Pariffin is an excellent neutron absorber, it's cheap, easy to get, and you can carve it into dinosaur shapes to play with after the fusion experiment is finished.
I see that others have done a good job in their replies. Let me just add the following:
The cavitation sites are produced by acoustic standing waves of high frequency. (I haven't heard how high, but it could be up the the megahertz range.) They are very short lived, and they grow and decay symmetrically, therefore there is no net translation, or flow, of the fluid and no 'sloshing.' I'm not sure why neutron irradiation promotes the fusion process, but the cavitation bubble wouldn't be affected by them except perhaps at the very last few picoseconds when the purported fusion would take place.
Cold fusion for Dummies?
We shouldn't allow this type of research to be shared. It should be owned by the United States alone.
My my, what other private property do you think should be taken over by you and the United States? How about Oak Ridge and Rusi Taleyarkhan control their property. It's so disheartening to realize how easily people assume a collectivist-state authority as opposed to individual authority.
Agreed.
It should be owned by the United States the inventor alone.
Having the US nationalize ownership is an act of theft. If anyone wants to use this technology, they must pay the inventor for it. Anything else is socialism.
Do we share this with the world, or capitalize on our inginuity and exploit it for every dime its worth?
I am a sick greedy capitalist so I vote to use it to put the likes of OPEC out of business, sanction its use to achieve our geo-political ends, and become stinkin filthy rich...what are your thoughts? I aplogize for being so subtle.
He might scale up a little, but commercial power generation seems unlikely. Still, a smaller power supply might be possible, one that would work aboard a satellite or space probe with many advantages, some political.
Well then, why not nationalize Colt, Beretta, Raytheon, Boeing, Lockheed Martin, Northrop Grumman, etc...? According to you, we should take their patents because they contain technology used for warfare.
Let's think about this. These people and businesses invest themselves, their time, their energy, their know-how. They spend money and effort to increase their capabilities. They spend money on R&D to discover new technologies.
Why do they do this? Is it just for fun? No. They expect to be paid for their work. In free countries, government doesn't just seize what it likes. It pays for it.
Do they work out of patriotism? Sure. But what is it about America do they find worth defending? Should they research weapons systems to fight off communist countries and their socialized economies, only to be subject to the same socialism they worked to defeat?
And lastly, think of the practical effects. You can't force people to invent things, to be creative, to innovate. Should businesses know ahead of time that inventions with military applications will be appropriated without compensation, they'll simply stop inventing them for lack of economic incentive.
For years, government has known this. They know nothing is more innovative and efficient as competitive capitalism. That's why they have left development of weapons systems largely to independent contractors. This wisdom has given the US technological advantage in todays battlefield and made us the superpower we are.
So government must pay this man for his invention. That is if it wants any more inventions in the future, and to retain the moral high ground against the enemies it uses these weapons against. If there is any legitimate claims of national security to be made, it should only be that he can't sell this technology to our enemies.
Would be nice...but they're a long way from producing power
I didn't say they shouldn't. They should not allow any of our enemies to read a journal and jump 5 years ahead in research though. The only benefit to publicly outlining the research is to get social "points".
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