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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

#281

Post by lambdatronics »

tsimionescu wrote: post #59
karmajunkie wrote: post #30

This is perhaps an obvious question to some, but I'll ask it anyway: How is the power generated here converted into usable electricity? I know for conventional fission reactors the heat of fission is basically used to run a steam turbine. Given the extreme heat of the plasma, and that it must be magnetically suspended so that it doesn't even touch the sides of the containment, how is that heat transferred to some oth…

Most of the answers are missing the actual (proposed) mechanism. The energy of the reaction is mostly carried away as high-energy neutrons. So, the way to get energy back is to "capture" those neutrons. Since neutrons are not electrically charged, you can't use them to directly create electricity, so all you're left with is using them for heat. Unfortunately, since they are electrically neutral, they're also relative…

Just to amplify on your point about lithium: the tritium production function is critical. Every fusion neutron needs to produce more than one tritium atom on average, so that the reactor is sustainable (there are inevitable losses & tritium also decays radioactively) or even making excess tritium (to bootstrap other reactors). This is challenging b/c even in the best case each neutron can produce maybe 2 tritium atoms, so there's not much margin. The lithium needs to comprise most of the material surrounding the plasma, limiting the fraction that's available for other functions (structural supports, heat shielding, cooling, plasma control & heating systems, sensors, etc).

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

#282

Post by yoz »

dr_dshiv wrote: post #240
dylan604 wrote: post #220

Earlier quoted context omitted.

>remember, this album is from a time when people bought CDs and probably stuck them into a one-disc player You just describe the first time I every danced with Lucy. I went back and forth with this disc and The Orb's A Huge Ever Growing Pulsating Brain That Rules from the Centre of the Ultraworld.

Same!

BEST HN THREAD EVER (and WOW is that an essential explanation of the first two Orbital albums)

is this where we talk about

- the 39:59 mix of The Orb’s “Blue Room” (which, like several other Orb singles, is better than the album version thanks to Jah Wobble providing a proper bassline)

- the academically-verified lack of repetitiveness in Autechre’s “Flutter”

- and Orbital’s “Criminal Justice Bill?” on the “Are We Here” CD single, which is four minutes of silence

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

#283

Post by yoz »

dylan604 wrote: post #179
mastersummoner wrote: post #177

Earlier quoted context omitted.

I've listened to that song hundreds of times yet somehow never realized it was Worf.

I didn't either, since I spelled it Warf! I never watched Star Trek (probably get my HN privileges revoked for that), but I did know that much. And then the Reading Rainbow guy's "whatever happened will happen again". I know the character's name is Geordie or whatever, but he didn't have the right accent for him to be a Geordie, so he will forever be Reading Rainbow guy instead.

> I know the character's name is Geordie or whatever, but he didn't have the right accent for him to be a Geordie

it’s a fair demand to make, given that his TV predecessor was called Scotty and DID have a Scottish accent

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

#284

Post by midasuni »

calfuris wrote: post #125
midasuni wrote: post #70

Earlier quoted context omitted.

Isn’t one of the problems with nuclear that it increases water temperature in rivers

That's a problem associated with a particular cooling system design, so it's more of a thermal power problem than a nuclear power problem.

Ok so wouldn’t it be a problem with a fusion/thermal system too?

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

#285

Post by dylan604 »

yoz wrote: post #282
dr_dshiv wrote: post #240

Earlier quoted context omitted.

Same!

BEST HN THREAD EVER (and WOW is that an essential explanation of the first two Orbital albums) is this where we talk about - the 39:59 mix of The Orb’s “Blue Room” (which, like several other Orb singles, is better than the album version thanks to Jah Wobble providing a proper bassline) - the academically-verified lack of repetitiveness in Autechre’s “Flutter” - and Orbital’s “Criminal Justice Bill?” on the “Are We He…

Funny thing about Blue Room, but that was the first time I had ever heard of Haile Selassie, then I was told that sample is a comedy bit from a prank call or whatever.

The Orb Live '93 CD was one of those that if a CD could wear out like a cassette, that would have been one (two technically) that would have from my collection.

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

#286

Post by onlyrealcuzzo »

cyberax wrote: post #273
onlyrealcuzzo wrote: post #255

Earlier quoted context omitted.

I feel like it's more like saying, we should build an airport here, because it's near a city and in a good location, and the land is cheap because no one else wants it for a number of reasons and this is the only thing that practically makes sense to go there. It's not going to save a meaningful amount of money. But that doesn't mean it's a bad idea.

Sure. But even in your example the site selection won't help you much to build the airport, you still need to do that, and it's still going to be massively expensive. I'm also in general skeptical about conversions of coal power plants into nuclear even for fission. Typical nuclear plants produce much milder steam temperatures and pressures than coal power plants, so their steam turbines are optimized for different c…

Isn't the grid interconnect way more valuable than the turbine?

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

#287

Post by egypturnash »

dylan604 wrote: post #220
egypturnash wrote: post #216

Earlier quoted context omitted.

It's two copies of "...where time becomes a loop." One on the left, one on the right. One of them is slightly shorter than the other, so that as they repeat again and again, they slide in and out of phase. The track ends after they come back into phase. If you listen to this with headphones, or speakers with decent separation, paying attention to this feels interesting. It's similar to the way listening to "binaural…

>remember, this album is from a time when people bought CDs and probably stuck them into a one-disc player You just describe the first time I every danced with Lucy. I went back and forth with this disc and The Orb's A Huge Ever Growing Pulsating Brain That Rules from the Centre of the Ultraworld.

Fifty-odd years old and I've still never acquired that stuff. Wonder what would be different if I had.

Those two albums sound like a pretty good soundtrack for making a good trip more likely!

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

#288

Post by QuantumG »

TaylorAlexander wrote: post #270
QuantumG wrote: post #192

Earlier quoted context omitted.

I expect they'd happily give access to anyone who wanted to cover it. Say, if someone wanted to do quarterly update videos, and had the appropriate skills, they'd only have to find the right person to ask, on the academic side. Hint.

Thanks. I do have the appropriate skills but I live in California and I’m busy with my own world changing projects that need videos produced about them! I just want to read blog posts about what’s happening.

Yep, be great if someone nearby had the inclination.

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

#289

Post by NovaDudely »

KyleBerezin wrote: post #172
NovaDudely wrote: post #159

Earlier quoted context omitted.

First thing that comes to mind is like twisted pairing on cables. Distributes the external/internal forces more equally. Is it anything like this?

No, twisted pair wires are really cool but different. When you push current down one wire you pull current down the other. The signal is passed through the differential of those 2 wires. If the wire is hit with EM interference, that change will be seen as a 'common mode voltage', that is, both wires will be 'pushed' or 'pulled' the same amount, and you won't see a differential. That effect works both ways too, where…

Thank you for the clear explanation! I love it!

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

#290

Post by onedognight »

nielsbot wrote: post #267
nielsbot wrote: post #211

Earlier quoted context omitted.

W7-X is a new stellarator design. It’s magnet arrangement was optimized using a lot of compute time and is designed to overcome the faults of previous more naive designs.

*its. ugh.

his, hers, theirs, its. No apostrophe. It took me 30 years to see this pattern.
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