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Wendelstein 7-X: Gigajoule energy turnover generated for eight minutes

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Re: Wendelstein 7-X: Gigajoule energy turnover generated for eight minutes

#81

Post by Eji1700 »

sdwr wrote: post #74
Eji1700 wrote: post #47

Earlier quoted context omitted.

I'm honestly not sure if you're joking but in case you're not, the "minimum viable size" is hardly the largest issue with what you're proposing and it sounds like you're not getting what the key issues are. You're talking about taking a technology that's so finicky we've barely gotten it to work after almost 100 years and rocketing it into space? We're no where near good enough at this to get a test that would work a…

That was not a real question, it was a subconscious plea for elon musk to take over and make it work. "Shooting it into space" is a reference to how SpaceX disrupted the rocket industry through a "fail fast" mentality, aggressive goals, and sheer force of will.

This take is even more baffling to me than the original question.

Re: Wendelstein 7-X: Gigajoule energy turnover generated for eight minutes

#82

Post by willis936 »

foolfoolz wrote: post #2

i’ve been following this project for 10 years. it’s been successful. but how do projects like these move faster? the wendelstein 7x is never going to generate usable electricity. it’s supposed to be the pre cursor to the producing reactor

HSX beat them to the punch by over a decade. Small is easy. Unfortunately no machine worth making (power generator relevant) is small. Practice helps.

Re: Wendelstein 7-X: Gigajoule energy turnover generated for eight minutes

#83

Post by willis936 »

b3orn wrote: post #61
hedora wrote: post #38

Earlier quoted context omitted.

Is there a minimum viable size for a fusion reactor? If it scaled down ennough, they could just launch prototypes into space, and see if they explode.

I'm no expert on this, but a minimum viable size exists and it's much larger than what you could just launch into space. I watched a video on this years ago, I don't recall the exact relation to size but if I'm not remembering this completely wrong there's a minimum size you need for a fusion reactor to "ignite", ITER is huge for a reason.

ITER is huge because it uses weak magnets.

Re: Wendelstein 7-X: Gigajoule energy turnover generated for eight minutes

#84

Post by starkrights »

Retric wrote: post #69
dale_glass wrote: post #64

Earlier quoted context omitted.

Odd units. 1 meter = 100 cm = 1000mm. So 1 millionth of a meter = 1/1000th of 1mm. thus, 100 millionths of a meter = 0.1mm, or ~4 thou in American units. Easily achievable by hobbyists, let alone by serious, professional equipment. Sure, that is a pretty exacting specification for what I suppose is a big machine, but I'm pretty sure very normal things like say, car engines get made to far tighter tolerances.

You messed up at your last step 1 millionth = 1mm, 10 millionth = 0.1mm, 100 millionth = 0.01mm 0.01mm is very difficult when you’re talking large custom objects with complex shapes.

I think the original commenter is right- correct me if I missed what you’re getting at.

Keeping it all in the same units until the end here:

1 millionth of 1 meter = (1 / 1,000,000)m = (1e-6m)

1 millionth * 100 = 100 millionths => (1e-6m) * 100 = (1e-4m) = 100 millionths

(1e-4m) = .0001m | 1m = 1000mm => .0001m*1000 = .1mm

Re: Wendelstein 7-X: Gigajoule energy turnover generated for eight minutes

#85

Post by stjohnswarts »

sdwr wrote: post #68
themagician wrote: post #63

Earlier quoted context omitted.

I find the geometry of things like this fascinating. We typically think in such simple shapes. I feel like my brain can do triangle, rectangle and maybe hexagons and that's about it. I remember when I finally understood radians enough to really understand circles and waveforms—I felt so enlightened. Like I actually remember the moment when it clicked. For years I was just "doing the work" without actually understandi…

I'll argue that "thinking in mobius" is simpler than thinking in circles, and more true to life than thinking in basic shapes. The core concepts in mobius-land are local curvature and global cumulative field.

Sorry those just aren't the way the average joe on the street thinks about things.

Re: Wendelstein 7-X: Gigajoule energy turnover generated for eight minutes

#86

Post by sp332 »

Dulat_Akan wrote: post #78

I am thinking why companies making so huge reactors, everything should be simple just for test to get energy

It's a been a long time, but in a talk at Google, I think Bussard said that power output scales with the 5th power of the radius of the device. There's really no point making a small one.

Re: Wendelstein 7-X: Gigajoule energy turnover generated for eight minutes

#87

Post by flotwig »

sdwr wrote: post #74
Eji1700 wrote: post #47

Earlier quoted context omitted.

I'm honestly not sure if you're joking but in case you're not, the "minimum viable size" is hardly the largest issue with what you're proposing and it sounds like you're not getting what the key issues are. You're talking about taking a technology that's so finicky we've barely gotten it to work after almost 100 years and rocketing it into space? We're no where near good enough at this to get a test that would work a…

That was not a real question, it was a subconscious plea for elon musk to take over and make it work. "Shooting it into space" is a reference to how SpaceX disrupted the rocket industry through a "fail fast" mentality, aggressive goals, and sheer force of will.

Please don't "move fast and break things" with nuclear fusion :-)

Re: Wendelstein 7-X: Gigajoule energy turnover generated for eight minutes

#88

Post by YossarianFrPrez »

Tuna-Fish wrote: post #17
YossarianFrPrez wrote: post #13

If I understand things correctly, the problem with magnetic confinement (e.g. Tokomaks, Stellarators) is that once you have heated a plasma such that it is "fusing," how do you get the power out with out cooling the very plasma you've just spent a lot of energy heating up? Helion, a fusion startup, claims to have solved this problem via capturing an induced current from colliding two hot plasmas together. I'd be curi…

Most fusion power systems assume they are doing that as neutrons. D-T fusion conveniently has the proportion of energy that gets lost from the plasma as KE of neutrons be pretty close to the amount of energy that a conveniently sized fusion reactor can afford to remove from the plasma. Then you trap the neutrons with, for example, a lithium blanket, use them to breed more tritium, and produce energy with a turbine fr…

Ah, got ya. Thanks for the information.

Re: Wendelstein 7-X: Gigajoule energy turnover generated for eight minutes

#89

Post by [deleted] »

alkonaut wrote: post #58
amelius wrote: post #24

Earlier quoted context omitted.

Isn't this similar to the monetary meaning of the word turnover? Like turnover : profit energy turnover : net energy output?

So when this had a turnover of 1.3 GJ (361 kWh), was that with a net loss in the end? How much electricity did they put in?

[deleted]

Re: Wendelstein 7-X: Gigajoule energy turnover generated for eight minutes

#90

Post by KyleBerezin »

Simon_O_Rourke wrote: post #72
KyleBerezin wrote: post #3

Ahh, Wendelstein is that stellerator reactor. The stellerator is really cool, and an alternative to a tokamak reactor. Tokamak is the doughnut shaped reactor, and it has a problem where the plasma near the outer circumference has less magnetic confinement. The stellerator is similar, but confines the plasma to a ribbon and folds it over on itself in a mobius-like arrangement. I used to be really interested in this, b…

Just curious as to why a Mobius strip type arrangement is better than a toroid? Is it anything to do with the turbulence in the plasma flow being easier to control?

These are great questions for someone more knowledgable, but as I understand it, If you follow a single point on the surface all the way around the loop, it will spend as much time in high confinement as it does in low confinement.

That explains why folding is important, as for the mobius, I oversimplified a bit. The Wendelstein has 5 folds, making it a mobius, but I think I read about one in Spain that had only 4 folds. That would mean the mobius isn't imperitive, but I'm sure there is a good reason for it.

Really a stellerator doesn't need 'folding' at all, they can be as simple as a twisted torroid. I didn't want to go into excruciating detail though, the more in detail I go the more likely I am to say something that is wrong lol.

Edit: I looked it up, the one in spain is called "TJ-II"

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