richard Dell interview -claims space propulsion breakthrough

[icarus]

Without a working fusion process/reactor any of these "studies" of fusion thrusters, transport to moon bases etc are just science fiction, cartoon engineering at best. Until the process is developed no-one has any idea whatsoever how the physical constraints on a thruster will pan out, it is a moot point they are beating.

Its like saying, "now we take 5 kg of unobtanium and then we ...."

If only half the energy of this whimsical dreaming went into actually solving the fusion problem things would be much further along, imo.

[chrismb]

...seconded...

"If we could find a way to print money without destabilising economies, then we could print extra money to fund research, fix world starvation, clean water for all, education, pay off the city bankers with a fortune, &c., &c., &c.... "

Is there really any point discussing what to do with extra money, until we have a way to generate it? What's the difference by asking 'what to do with extra energy'. We know damned well what it can do. More time spent looking at all fusion experimentation and picking out winning ways to go, that people jumping on energy gravy-trains by spouting bullshyte any 13 year old sci-fi fan could write for himself.

[rjaypeters]

If only half the energy of this whimsical dreaming went into actually solving the fusion problem things would be much further along, imo.

What you and chrismb want would actually require talent and hard work. Both are available, but really hard to put together.

[chrismb]

If only half the energy of this whimsical dreaming went into actually solving the fusion problem things would be much further along, imo.

What you and chrismb want would actually require talent and hard work. Both are available, but really hard to put together.

I would certainly go along with that. I think the 20th Century was blessed with people that fitted into both of those categories. Now it's made too easy for clever people to set themselves up in a cushy gravy-train acedemia environment, or find government funding and dabble along at a pace that is one single basis point above just-acceptable.

There is no motivation for the talented to work very hard, because if you are a hard-working talent then you have no time for self-aggrandisement and self-promotion. These things are essential now, else no-one lets you to the front of the crowd even if you have the 'answer' that the crowd is looking for.

I do tend to think that the 50's and 60's were a completely different era of technology culture. It seems apparent, from media of the day, that the rest-of-society [inc. government] went looking for those talented hard-workers who were so busy that they were tucked up in their labs all the time! Nowadays, one not only has to be brilliant, but also great at smooching the public, politicians and capitalists in a way that just wasn't necessary [or expected] in the 'good-ol'-days' of the golden scientific era.

I think I could name you several 'reclusive' world-class scientists from that period that hated appearing in public and resented being pulled away from their lab work. Can anyone name any such 'reclusive' scientist these days?

[nextbigfuture]

They are starting with Q< 1 devices that are better than current ion thrusters. Space applications are less demanding than power generation.

It is much easier to develop fusion powered spacecraft than fusion power energy.

Current launch costs are $2000-20,000 per pound. Propulsion beyond orbit is also not very good and the station keeping for satellites is also not so good. For launch the system would only need to work for a few minutes. For beyond orbit there can also be lower reliability versus fusion to power the world. Fusion to power the world would take many tens of gigawatts to begin to have an impact. A few tens of megawatts and you have revolutionized space travel for trips to Mars.

So fusion for space travel first because it is thousands of times lower demands to have a huge impact. Thousands of times less power, can be thousands of times more expensive, can work for shorter times and less reliably, and there would be less environmental study and legal issues.
the downside for space applications is space rating and weight, but IEC fusion can have very low weight and can scale down.

Of course EMC2 or these others can crack power generation too all the better.

George Miley has been building IEC fusion systems for a long time. The work is there. It is just a different approach.

EMC2 is funded by the Navy so they need a particular kind of reactor to meet their applications (powering destroyers, frigates and air craft carriers and submarines)

The ISS (Space station) uses 8 tons of fuel per year to maintain orbit. 8000 lbs. It costs $2000-20,000 per pound. $16 million to $160 million to launch fuel. Same kind of situation for communication and other satellites. An early version of this that is better than an ion thruster could reduce fuel demand down to 600 lbs.

100 KW to 1 MW systems would be a big early market

http://nextbigfuture.com/2011/01/iec-th ... ering.html

http://nextbigfuture.com/2011/01/review ... ed-in.html

[chrismb]

George Miley has been building IEC fusion systems for a long time.

...I suggest it's probably a good time for him to give up, then, if he still has no practical bit of kit he can hand over to someone to test out and/or make use of.

As I suggested, self-aggrandisement appears to be a necessary feature in the current culture of gravy-train science, and to best achieve that function it is consequent that they displace others in a manner that others can't make gains for real attention over their own work.

This debate has run here before and replies to this line of mine tend to run along the line of 'everyone can join in'. But, y'know, there's only so much space at the front of the crowd and if the ones there already like it then they won't want anyone else getting attention. It is just the way of human nature. Attention is distracted away from the talented and hard-working, when there are so many blaggers and schmoozers who have pushed their way to the front with tall stories of romantic notions of intergalactic travel.

George Miley has never acheived anything better than Q>1e-7, so I don't see that saying 'Q< 1 devices that are better than current ion thrusters' covers any work he has attempted.

...just my opinion...

[GIThruster]

George Miley has been building IEC fusion systems for a long time.

...I suggest it's probably a good time for him to give up, then, if he still has no practical bit of kit he can hand over to someone to test out and/or make use of.

As I suggested, self-aggrandisement appears to be a necessary feature in the current culture of gravy-train science

Chris, Miley is not a self-agrandizing guy. He's a very humble guy. The interview was with the business guy, Dell; who is looking to commercialize Miley's work.

Your beef is not with Miley. After all, he didn't give the interview.

Real issue is, did Dell over-promise and under-deliver? Doesn't seem so to me. He's saying what he thinks will happen in the next two years. As much as i personally do not like Dell, I can't say he did anything wrong here. If he's wrong so what? I didn't see him asking for money.

IIRC, Miley is Emeritus, has earned his free lab space through decades of teaching at Urbana and isn't looking for money. He's just looking for results. How can you have a beef with that?

[ladajo]

Brian,
Do you know if anyone is going to take another crack at interviewing Rick Nebel now that they are doing test runs on WB8?
OBTW, the IXL/EXL diagram in Miley's PPT looks like he pulled it directly from a Bussard report from a ways back.

Thanks.

[D Tibbets]

Actually, D-He3 fusion is aneutronic by definition. It is a lose definition, but if < 1% of the fusion power output comes from neutrons, it is defined as aneutronic. D-He3 can achieve this by having moderate excess He3 in the mix so that D-He3 fusions dominate over the D-D fusions. Compare this to D-T fusion in which 80% of the power comes from even harder to shield high energy neutrons, or D-D fusion which is at ~ 50%.

Still, that is a lot of neutrons, especially compared to P-B11 which one quote was that the neutron outputs are less than a part per million. Still at hundreds of Megawatts, this has to be shielded (just not as much). In this case I understand that side reaction gamma ray production is more dangerous (perhaps 1part per 10,000.).
Having said that, looking at the size of the ships compared to a Space Shuttle, they are going to have a lot of distance shielding, perhaps as much as a kilometer.

Dan Tibbets

[quixote]

The ISS (Space station) uses 8 tons of fuel per year to maintain orbit. 8000 lbs. It costs $2000-20,000 per pound. $16 million to $160 million to launch fuel. Same kind of situation for communication and other satellites. An early version of this that is better than an ion thruster could reduce fuel demand down to 600 lbs.

That'd be 16000 lbs (1 ton is 2000 lbs). So $32m to $320m.

[GIThruster]

That's so far off it makes me laugh. ISS uses more like $500 million/year in propellants but I'd need to check.

[zapkitty]

ISS specific: it would seem that even at 10 times the thrust of other ion thrusters this concept would still involve continuous thrust periods and given the ISS primary role of microgravity research any low thrust long duration drives are contraindicated... whether the ions be propelled by solar-powered grids or fusion processes.

[93143]

If the ISS had a thruster that produced no more thrust than was necessary to counteract drag, they could run it continuously and get an environment much closer to zero-gee than they have now with the engines off. Provided it didn't induce significant vibration, of course, and provided (in the case of an electric thruster) power could be made available to run it...

Also, reactor shielding isn't the big reason to go with aneutronic reactions. In fact, if Wikipedia is right about those gammas, p-¹¹B could prove harder to shield than D-T. The big draws are (1) direct power conversion, and (2) superior component lifetime under neutron bombardment. Reducing neutronicity from 0.8 to 0.05 has a very small effect on the required shield thickness (it's logarithmic, you see), but the neutron damage lifetime of a given core component is multiplied by 16.

[chrismb]

I've long-advocated the p-15N reaction because a) it is a gaseous/gaseous fuel, very easy to handle, b) if you can do p-11B then p-15N really shouldn't be that much more difficult, c) there are no reported neutronic outcomes - really aneutronic d) the reaction output is modest, so that the alphas are a few less MeV than those out of p-11B, and the p-11B alphas may have sufficient energy to start activating various first-wall materials that you might want to use.

No-one has ever repeated my p-15N suggestion, that I have noticed, but if you really want to talk about the long-term implications for all of this, then take a look at p-15N. Not such good outputs, but very clean and very easy to handle the non-toxic gaseous fuels to a degree that wanting to use p-11B looks almost irresponsible!

[Diogenes]

Without a working fusion process/reactor any of these "studies" of fusion thrusters, transport to moon bases etc are just science fiction, cartoon engineering at best. Until the process is developed no-one has any idea whatsoever how the physical constraints on a thruster will pan out, it is a moot point they are beating.

Its like saying, "now we take 5 kg of unobtanium and then we ...."

If only half the energy of this whimsical dreaming went into actually solving the fusion problem things would be much further along, imo.

This was my first thought upon reading the article(s).