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Dr. Bussard Passes Away, Polywell Fusion Continues
Vinz writes "Dr Bussard, the man behind the Bussard Collector and inventor of the Polywell fusion device, passed away last Sunday in the morning. He leaves behind him a legacy of EM fusion devices, and a team determined to continue his efforts. The news of funding extension for the construction of his WB-7 fusion devices made it to slashdot months ago (as well as his talk at google). They may be a serious candidate in the run to bring commercial fusion, and may work at lower scales than other projects. Let's hope the project continues in good shape despite his departure."
With no Bussard, where are starships going to get their blinky engine lights from?
Bow-ties are cool.
I hope they cremate him in a fusion reactor. I'm sure it's hot enough.
"There are more things in heaven and earth, Horatio, than are dreamt of in your philosophy."
It's referenced in the summary. I hadn't heard about Bussard or the polywell. It sounds promising. Navy-funded research too. I'm sorry this person died before he could see it through to demonstration. Hopefully this really works.
http://en.wikipedia.org/wiki/Polywell Ouch. In terms of value for money, though, gambling our money away on a wild scientific flier would be a much better investment than starting the war in Iraq.
The other thing that caught my attention was Bussard's comment that they should go straight to full scale. He may or may not be right. Most people who have been around the block more than once would be sceptical though. When you are trying something new, there is almost always a gotcha or two.
Dr Bussard, the man behind the Bussard Collector and inventor of the Polywell fusion device, passed away last Sunday in the morning.
He didn't simply pass away. He was a victim of entropy.
The theory of relativity doesn't work right in Arkansas.
The catch to these devises appears to be that if you have a strong enough electrostatic field to contain the ions then you will also lose A LOT of high energy electrons (Rider 1995), thus reducing the confinement efficiency. As Rider notes, capturing the escaping electrons to recover their energy may make the scheme feasible for D-T fusion ( there are other issues as well however).
Personally I think stellarators are more promising. For those who don't know stellarators are a bit like Tokamaks, except rather than relying on an electric current in the plasma to create the necessary twist to the magnetic field for confinement, they twist the confinement vessel itself ( a bit like a moebius strip ), making them a lot more stable than Tokamaks, and allowing them to operate continuously (You can't induce a DC current in the plasma so Tokamaks necessarily operate in pulses ). Main problem seems to be that since stellerators have a lot less symmetry than Tokamaks the calculations become more difficult, but if computing power continues to rise this will probably be solveable.
As a bonus stellarators look damn cool ; )
http://www.efda.org/pictures_html/stellarator_schema_and_live.jpg
http://www.psl.wisc.edu/hsx.jpg
Linking to Wikipedia is sheer laziness. I'm surprised "passed" and "away" weren't Wikipedia links.
Even a simple Google search for (polywell && "dr. bussard") turned up a variety of sources, including http://www.talk-polywell.org/
I want to drag this out as long as possible. Bring me my protractor.
Cue the inevitable silly poster who chastises us all for making jokes about someone's death, and the +5 Insightful reply explaining how laughter is a way of coping. Don't forget the meta-comments describing the very phenomenon ;D!
"may work at lower scales than other projects"???? - One of the main reasons for pushing for the WB7 model was that they couldn't get positive net energy at small scales. The prediction was that they'd need something on the size of a standard fission reactor to see viable energy output. Plus, the design team originally modeled all the coils with as a zero thickness circle and couldn't understand that when they built the thing that the coil circle centers had to be spaced apart which caused field losses. After seeing stupid design errors like that, I don't have much faith in the research team, but still the concept is worth investigation.
From the wikipedia article:
In principle, the Bussard ramjet avoids this problem by not carrying fuel with it. An ideal ramjet design could in principle accelerate indefinitely until its mechanism failed. Ignoring drag, a ship driven by such an engine could theoretically accelerate arbitrarily close to the velocity of light, and would be a very effective interstellar spacecraft.
So what would happen to people or computers travelling inside the ship?
Would they move forward through time at accelerated speed? or end up in deep-space oblivion?
He who knows best knows how little he knows. - Thomas Jefferson
.."inventor of the Polywell fusion device, passed away last Sunday in the morning. He leaves behind him 2 long flaming tyre tracks and a mysterious note about Libyans"
I read about Polywell about two months ago here. After doing some research on it, I was very much enthusiastic about what I found out and wanted to build a website that would look more professional than the one the polywell folks currently have. At that time, they were still trying to find funding and/or investors, and it was my belief that having a real website, like a lot of energy companies and other places where people have ideas that need funding, would help out. I built one, with the idea that even if they decided not to use it, it would still work as a community forum. I am still trying to get a lot of the information exactly the way I want tit, but the website is here: http://www.xevioso.com/projects/polywell Unfortunately, after I sent the message to Dr. Bussard about a month ago to take a look at what I was building, he basically said that while it was a great site, it wasn't going to be useful to them int he near future because of some things coming down the line that would make it unneccesary. Of course, one month later, the Navy resumed funding. And now Dr. Bussard has passed on. In any event, if people would like to get some good information about this project, please visit the link above.
I thought Larry Niven named the matter scoop after Bussard -- in his Known Space novels and stories, there are frequent references to "Bussard Ramjets", a fictional propulsion system consisting of an electromagnetic scoop that collects hydrogen from space, and a fusion-powered rocket that uses some of the hydrogen for nuclear fusion, and uses the remainder as reaction mass. I'm pretty sure this was long before STtNG.
The Bushard ramjet is a central piece of technology in Larry Nivin's "Known Space" A universe that encompasses the bulk of Nivins stories. In fact one of the the Halo video game series shares allot of similarities with the Ring World series.
---In a time of Chimpanzees I was a Monkey.
Passes away? He DIED! d-i-e-d-!!
The other thing that caught my attention was Bussard's comment that they should go straight to full scale. ... Most people ... would be sceptical... When you are trying something new, there is almost always a gotcha or two.
In this case he believed he had the scaling laws down. With power proportional to the seventh power of the radius and energy gain proportional to the fifth power, you were only talking about building a device maybe 10 times the radius of the lab device. That's TINY as fusion experiments go, and also compared to fission plants. And the thing is basically a slightly gassy vacuum tube with some magnets in it, i.e. mostly empty space, very little material.
If there are any gotchas you'd have to scale it up about that much to find them. So why go halfway and then build a full-size one when, if it turns out there AREN'T any gotchas you've got an operating power plant on the next step?
His plan was to do two more small prototypes, to get some more solid data than his three-neutron final run and compare two geometries for the final deaign, then go for the gotchas-or-gold. If it works, it gets you to production right away and you didn't spend a dime on yet another intermediate prototype. If it doesn't, you're not out all that much more than if you built some intermediate size that was maybe big enough to find the gotchas.
Suppose there AREN'T any gotchas. Then we get to working fusion power years sooner. Ditto if there are gotchas that only show up at the scale between the intermediate prototype and the full-size design. In either case the time spent on the middle-size below-break-even prototype was wasted.
Baby steps are for people who get their money from researching and will be looking for a new job once things are actually working. Big steps are for people who want to get to the finish line.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
He gave a presentation about his research to Google. A little long, but I found it interesting. http://video.google.com/videoplay?docid=1996321846673788606
He "passed away"?? You mean he died, right?
This is not to diminish his other work and Bussard may have accomplished other good engineering work, but if anybody should get credit for the "Bussard collector", it should be the people making it actually work eventually. If it ever does work, the amount of brilliance that needs to go into the engineering (not to mention getting the funding!) will be far greater than the initial idea, an idea probably many people would have come up with by then independently.
His work on the Polywell is different: there he sat down to do get the funding and do the engineering and implementation himself. That's the really tough work. Unfortunately, after 12 years, results are still inconclusive, which raises the question whether the concept itself may be flawed.
I know it is a bit off topic, but seeing as we are discusing confinement, I would love to hear someone comment on Leslie Woods' (a late mathematician from Oxford) equations. Basically, from what I understand from the Nerenberg lecture he gave, he claimed that the majority of the gap between what the equations predict and what is observed in reality is not due predominantly to missing turbulence, but rather to a missing non-turbulence term.
Unfortunately, from what I understand of what he said, despite his corrected equations predicting very closely what has actually been observed in practise, and turbulence approaches not predicting anything very well beyond their degrees of freedom, the current community (or at least a key subset of it with a lot invested in the turbulence approaches) is uninterested in hearing anything more about it or allowing the work to be published. Apparently they forstall under such issues as demanding it be derived from Boltzmann's equations, despite his objections that this cannot be done due to the fundamental assumptions underlying Boltzmann's equations.
Personally, although I do not have the physics background to comment on the derivation, I must admit that, if the equations are indeed doing a much better job of matching up with what is being observed, I am quite bothered to hear this. I am reminded of such issues as those between Laplace and Fourier regarding the latter's (seminal) work on the Fourier series and the former's repeated objections to it or anything to do with it. Really, shouldn't the final test always be how well it does in the lab? I hate to think of all that great plasma engineering that is being help up over lack of ability to really model these phenomenons well in the lab.
I remember when they would talk about Bussard collectors that would collect hydrogen for fuel for their fusion reactors. I never made the connection then but now I do. Amazing! I really hope fusion comes into play this century. Fission is so messy and dangerous. I think my kids kids kids will have them as regular appliances in their homes. Man, can you imagine the energy savings!?!
I loved the Niven known space series with the Bussard ramjets.
After reading through the presentation and arguments above I have not no hope that his polywell device will work. I guess we might have more info some time next year.
Tau Zero by Poul Anderson is a good sci-fi story about a ship with a Bussard Ramjet getting really out of hands. Basically, due to an accident the crew of a spaceship are stuck on accelerating forever, fly into intergalactic void, creep ever closer to the speed of light and experience sufficiently serious time dilation to eventually notice that there are no new stars forming anymore, galaxies are getting dimmer as the old stars start to fade away and to top it all, the universe has become old enough to start contracting towards the Big Crunch. (The story doesn't end there, but I'll leave the ending unspoiled)
Everyone who makes generalizations should be shot.
When I worked on NASA contract for Dr. Dana Andrews at Boeing's Kent Space Center, in the slot later filled by Dr. Robert Zubrin, we were tasked with studying all known forms of fission and fusion and more exotic space propulsion. My friend Dr. Robert Forward worked the equivalent contract for USAF.
Hence we looked long and hard at the Bussard Ramjet. At this time the word on the street was that drag killed the Bussard Ramjet. That the Bussard Ramjet was actually an elaborate interstellar parachute.
I was responsible for several chapters of our report to NASA, including the one on Fusion propulsion.
In re-thinking Bussard's design, I looked at large superconducting rings carrying large currents, and how they would interact with planetary, solar, and galactic magnetic fields.
This included study of the earlier "ringsat" by James B. Stephens at JPL, a prolific inventor (in fact, #2 of all time at JPL) who pased away last year.
One issue was, could plasma pouring through the ring generate electric power to run ion propulsion?
The modeling got sticky. After I left and was quickly replaced by Dr. Robert Zubrin, our qualitative early model was replaced by the correct plasma physics equations, and Andrews & Zubrin are credited with inventing the Magnetic Sail.
My sometimes work with Dr. Robert Forward (see for instance the piece on slower-than-light edited by Dr. Geoffrey Landis on an interview with me, Forward, and Dave Brin) ended with Bob Forwards death from brain cancer.
I have since worked with Bob Zubrin (coauthoring his first novel and screenplay, but taking a cash bonus for removing my name from ther title pages).
I have know Larry Niven for a very long time, and adore his use of Bussard's star drive in science fiction.
One coincidence: Larry Niven, Dana Andrews, Dave Brin, and I all were students at Caltech, which administered JPL where Jim Stephens worked.
Hence all of this involves super-smart hard-working quirky people on the fuzzy boundary between science and science fiction.
When the sun expands and vaporizes the biosphere, Robert Bussard's atoms will flow out into the interstellar medium, where his mind had long ranged free.
-- Prof. Jonathan Vos Post
I lol'd. An internet to you, good sir.