4 ms·

I'm not keen on the idea of applying a 'keep subtracting things until it blows up' mentality to fusion reactors.

by ortusdux 1y ago

bhaak 1y ago
The nice thing about fusion reactors is that they don’t blow up but just don’t work anymore.
- soperj 1y ago
  they have fission reactors that have done that since the 60s (CANDU Reactor). They just don't help you produce nuclear bombs...
  - greesil 1y ago
    I dunno dude, if you fuse tritium and deuterium it does make neutrons.
  - philipkglass 1y ago
    CANDU has low intrinsic nuclear proliferation resistance. It can run on natural uranium, so it's easier to fuel than light water reactors which need enriched uranium, and its online fuel-swapping design means that it's easy to switch to low-burnup operation for generating weapons grade plutonium. Current CANDU power reactors have extensive monitoring to confirm that they are used peacefully, but if e.g. South Korea had a security crisis and decided to pursue a crash nuclear weapons program, world opinion be damned, its CANDU based reactors at Wolseong could be quickly reconfigured for weapons purposes: https://en.wikipedia.org/wiki/Wolseong_Nuclear_Power_Plant https://en.wikipedia.org/wiki/Wolseong_Nuclear_Power_Plant
    - perihelions 1y ago
      It's topical that India's nuclear weapons program was started up with a Canadian-supplied heavy water reactor (though not CANDU; a not-power-generating type). https://en.wikipedia.org/wiki/CIRUS_reactor https://en.wikipedia.org/wiki/CIRUS_reactor > "Canada stipulated, and the U.S. supply contract for the heavy water explicitly specified, that it only be used for peaceful purposes. Nonetheless, CIRUS produced some of India's initial weapons-grade plutonium stockpile,[6] as well as the plutonium for India's 1974 Pokhran-I (Codename Smiling Buddha) nuclear test, the country's first nuclear test.[7]"
xorxornop 1y ago
I wouldn't be concerned about this, personally, for the precise reason that it is a fusion device - not fission! Fusion is incredibly difficult just to start, let alone keep burning - unlike fission, which is only too happy to enter runaway conditions if not very carefully regulated. Fusion is like a little ember in your fireplace you have to carefully blow on to keep alight; fission is like keeping a fireplace lit by pouring gasoline into it.
- grues-dinner 1y ago
  I'd say (older-generation) fission is more like having an indoor swimming pool filled with burning gasoline, but keeping the windows shut so there's only enough air for it to burn at the rate you want to heat the house.
  - HPsquared 1y ago
    Or a swimming pool full of those spicy rocket propellents discussed in the book Ignition! which have combustion products like hydrogen fluoride.
    - exe34 1y ago
      "Things I will not work with" - "at this point hydrogen fluoride loses its gentle nature".
    - sheepscreek 1y ago
      Would love to take a look at your library.
      - FiatLuxDave 1y ago
        Not the poster above, but as someone who also has a copy of Ignition! in their library, I think you might enjoy the pdf version: https://library.sciencemadness.org/library/books/ignition.pdf https://library.sciencemadness.org/library/books/ignition.pd...
    - 1y ago
IlikeKitties 1y ago
I mean, it's expensive but there's nothing that can happen, they just stop working the nanosecond the environment isn't just right.
- Cthulhu_ 1y ago
  It'll be expensive, but will it be more expensive than the costliest disaster ever, Chernobyl, which apparently cost (is costing) $700 billion to contain / clean up?
  - IlikeKitties 1y ago
    No,... so?
_joel 1y ago
That's not what they're doing though. Reducing manifolds actually improves the durability.
GMoromisato 1y ago
You could probably summarize the history of bridge-building as "keep subtracting things until they don't stand up anymore." Building bridges (and large structures in general) has always been about the tension between over-engineering (for safety) and under-engineering (for cost/aesthetics). The Brooklyn Bridge is massive; they'd never built a bridge like that so they over-engineered it. But once they saw that it was more than strong enough to stand up, the next bridge was lighter. And the next one after that was even lighter. And so on, until a bridge collapses because some new factor came into play (e.g., harmonic resonance). Source: To Engineer Is Human by Henry Petroski--one of my favorite engineering books.
- cjbgkagh 1y ago
  Not read the book but I thought the Brooklyn Bridge was over specified on the wire strength because they knew the corrupt supplier would circumvent quality control to supply them with substandard material.
- drob518 1y ago
  When I was an engineering summer intern at HP, they had all the interns do a side project of building a bridge (model sized). The designs would be judged by stacking bricks on the bridges and then dividing the max count of bricks before failure by the weight of the bridge. Most interns, myself included, over engineered our designs. One intern “got it” and submitted a bridge that was built out of just a few pieces of balsa wood. It only held one or two bricks before snapping, but it was ultra-light and won the competition. That exercise always stayed with me. Engineers always need to focus on the correct priorities and understand when “enough is enough.”
vjvjvjvjghv 1y ago
You should be keen on that idea. Simpler designs are usually more reliable. And a fusion reactor doesn't really blow up. It's hard enough to make it do something.
andrepd 1y ago
Fusion is incredibly safe with none of the risks of runaway reactions like in fission.

I'm not keen on the idea of applying a 'keep subtracting things until it blows up' mentality to fusion reactors.

bhaak 1y ago

The nice thing about fusion reactors is that they don’t blow up but just don’t work anymore.

soperj 1y ago
they have fission reactors that have done that since the 60s (CANDU Reactor). They just don't help you produce nuclear bombs...
- greesil 1y ago
  I dunno dude, if you fuse tritium and deuterium it does make neutrons.
- philipkglass 1y ago
  CANDU has low intrinsic nuclear proliferation resistance. It can run on natural uranium, so it's easier to fuel than light water reactors which need enriched uranium, and its online fuel-swapping design means that it's easy to switch to low-burnup operation for generating weapons grade plutonium. Current CANDU power reactors have extensive monitoring to confirm that they are used peacefully, but if e.g. South Korea had a security crisis and decided to pursue a crash nuclear weapons program, world opinion be damned, its CANDU based reactors at Wolseong could be quickly reconfigured for weapons purposes: https://en.wikipedia.org/wiki/Wolseong_Nuclear_Power_Plant https://en.wikipedia.org/wiki/Wolseong_Nuclear_Power_Plant
  - perihelions 1y ago
    It's topical that India's nuclear weapons program was started up with a Canadian-supplied heavy water reactor (though not CANDU; a not-power-generating type). https://en.wikipedia.org/wiki/CIRUS_reactor https://en.wikipedia.org/wiki/CIRUS_reactor > "Canada stipulated, and the U.S. supply contract for the heavy water explicitly specified, that it only be used for peaceful purposes. Nonetheless, CIRUS produced some of India's initial weapons-grade plutonium stockpile,[6] as well as the plutonium for India's 1974 Pokhran-I (Codename Smiling Buddha) nuclear test, the country's first nuclear test.[7]"

xorxornop 1y ago

I wouldn't be concerned about this, personally, for the precise reason that it is a fusion device - not fission! Fusion is incredibly difficult just to start, let alone keep burning - unlike fission, which is only too happy to enter runaway conditions if not very carefully regulated. Fusion is like a little ember in your fireplace you have to carefully blow on to keep alight; fission is like keeping a fireplace lit by pouring gasoline into it.

grues-dinner 1y ago
I'd say (older-generation) fission is more like having an indoor swimming pool filled with burning gasoline, but keeping the windows shut so there's only enough air for it to burn at the rate you want to heat the house.
- HPsquared 1y ago
  Or a swimming pool full of those spicy rocket propellents discussed in the book Ignition! which have combustion products like hydrogen fluoride.
  - exe34 1y ago
    "Things I will not work with" - "at this point hydrogen fluoride loses its gentle nature".
  - sheepscreek 1y ago
    Would love to take a look at your library.
    - FiatLuxDave 1y ago
      Not the poster above, but as someone who also has a copy of Ignition! in their library, I think you might enjoy the pdf version: https://library.sciencemadness.org/library/books/ignition.pdf https://library.sciencemadness.org/library/books/ignition.pd...
  - 1y ago

IlikeKitties 1y ago

I mean, it's expensive but there's nothing that can happen, they just stop working the nanosecond the environment isn't just right.

Cthulhu_ 1y ago
It'll be expensive, but will it be more expensive than the costliest disaster ever, Chernobyl, which apparently cost (is costing) $700 billion to contain / clean up?
- IlikeKitties 1y ago
  No,... so?

_joel 1y ago

That's not what they're doing though. Reducing manifolds actually improves the durability.

GMoromisato 1y ago

You could probably summarize the history of bridge-building as "keep subtracting things until they don't stand up anymore." Building bridges (and large structures in general) has always been about the tension between over-engineering (for safety) and under-engineering (for cost/aesthetics). The Brooklyn Bridge is massive; they'd never built a bridge like that so they over-engineered it. But once they saw that it was more than strong enough to stand up, the next bridge was lighter. And the next one after that was even lighter. And so on, until a bridge collapses because some new factor came into play (e.g., harmonic resonance). Source: To Engineer Is Human by Henry Petroski--one of my favorite engineering books.

cjbgkagh 1y ago
Not read the book but I thought the Brooklyn Bridge was over specified on the wire strength because they knew the corrupt supplier would circumvent quality control to supply them with substandard material.
drob518 1y ago
When I was an engineering summer intern at HP, they had all the interns do a side project of building a bridge (model sized). The designs would be judged by stacking bricks on the bridges and then dividing the max count of bricks before failure by the weight of the bridge. Most interns, myself included, over engineered our designs. One intern “got it” and submitted a bridge that was built out of just a few pieces of balsa wood. It only held one or two bricks before snapping, but it was ultra-light and won the competition. That exercise always stayed with me. Engineers always need to focus on the correct priorities and understand when “enough is enough.”

vjvjvjvjghv 1y ago

You should be keen on that idea. Simpler designs are usually more reliable. And a fusion reactor doesn't really blow up. It's hard enough to make it do something.

andrepd 1y ago

Fusion is incredibly safe with none of the risks of runaway reactions like in fission.