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Is Iron man's power source achievable in today's age? Or is just fiction that we can do something that small? (lemmy.world)
submitted 1 month ago by Patnou@lemmy.world to c/askscience@lemmy.world
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[–] Dookieman12@piefed.social 12 points 1 month ago (3 children)

Canonically, the arc reactor is a nuclear fusion reactor. Nuclear fusion is possible, the sun does it constantly. It's possible on Earth, scientists have done it many times. However, none of those fusion reactions have produced more energy than it took to make them happen yet.

The fusion reactors we do have are the size of large buildings. The idea of picking one up and moving it around is like the idea of picking up a whole power plant and moving it around. The idea of holding it in the palm of your hand, while theoretically "possible", wouldn't be achievable with today's technology by any stretch of the imagination.

Maybe another 100 - 1,000 years.

[–] irotsoma@piefed.blahaj.zone 5 points 1 month ago (2 children)

Also, it's good to note, that producing that much power in a small device would mean that device is very, very volatile. There was some research I read about a long time ago to design a small nuclear fission device that would ideally replace batteries with a much more long lasting energy cell that also would greatly increase output wattage. Besides the obvious miniaturization issues, the other problem was that if that much energy is release all at once, such as from a drop or being in a fire or something else catastrophic, the explosion it would create would be significant and do a lot more damage than any battery not to mention the heavy shielding itself as shrapnel would be way more destructive than the explosion alone.

Take that and then think about people who are likely to use these things as weapons and you can't really sell that kind of thing commercially. This is one reason that for example, gasoline is not more energy dense which would make it way more efficient. Imagine if gasoline was as energy dense as jet fuel. It would mean way smaller fuel tanks and thus significantly less weight both of the tank and the fuel and thus more efficient cars. But the danger in widely selling jet fuel to consumers is significant.

[–] Dookieman12@piefed.social 11 points 1 month ago (1 children)

Jet fuel is available for purchase at the consumer level without regulations because people have private planes.

Jet fuel (ATF or avtur) is also called "aviation kerosene" and is similar enough to diesel fuel that it can used in diesel engines. Kerosene and diesel are also readily available most places.

Aviation gasoline (or avgas) is just ordinary leaded gasoline, which was available for a long time to consumers until it was banned for environmental reasons.

Gunpowder and tannerite are available over the counter, no regulations there either.

[–] irotsoma@piefed.blahaj.zone 4 points 1 month ago

I don't want to get into guns, that's a special case in the US due to money in politics.

But, ok, yeah "jet fuel" I was thinking more of military jet fuels, I was in the Navy for a while and never in the aviation industry. Though even they don't approach the energy density and instability a reactor would have. Maybe I should have said "rocket fuel" or even pure hydrogen. Anyway, point is cars could use fuels that are more energy dense, but even missiles don't use the most energy dense fuel available because there's a need to balance stability and potential for explosions with energy density.

A miniaturized fission reactor like I mentioned or even more, a miniaturized fusion reactor like in Ironman, would have problems if sold unregulated, both in accidents as well as malicious use as a weapon.

[–] CompactFlax@discuss.tchncs.de 3 points 1 month ago (1 children)

Jet fuel is way less volatile and way less dangerous than gasoline.

[–] DrinkMonkey@lemmy.ca 4 points 1 month ago (1 children)

My high school science teacher took a container of jet fuel, poured it into a beaker, then suited up in a tin foil apron, face mask, safety everything, ducked behind his large lab bench at the front of the class, lit a popsicle stick on fire, grabbed it with tongs, and dropped it into the beaker while everyone in the front row scrambled. Made a big show of it. It went out without even a fizz.

Then he transferred it into a small spray bottle and aimed it at the same lit popsicle stick on the end of the same tongs and made a highly satisfying fireball.

Then he switched a shop vac from suck to blow, attached some kind of paint sprayer contraption, and made a giant flame thrower that scorched the ceiling tiles. It was awesome.

The next years’ classes didn’t get the same experience. Can’t imagine why.

[–] Bougie_Birdie@piefed.blahaj.zone 1 points 1 month ago

High school science story time:

When I was in school, we had a gym teacher fill in for the chemistry teacher. Not as like, a substitute teacher for a day or a week or whatever, but due to some kind of staffing or budget issue the gym teacher taught that whole semester. His science background would have been what he learned in high school himself thirty years earlier, but he was a warm body that could read a textbook so that was good enough for the administration.

Anyway, there was this demonstration they'd do where they'd drop a chunk of sodium in water, and as an alkali metal it reacts with heat, sparks, and maybe a small explosion. Now, you're only supposed to use a tiny amount for the demonstration, so the teacher pulls out their chunk of sodium and cuts off a pea-sized piece for the experiment and wows everyone with the demonstration.

Every year you get at least one student who asks what happens if you used a larger piece. The chemistry teacher would explain about how the reaction scales up, and that it's too dangerous to perform in the classroom. But the gym teacher says, "Gee, I don't know. But this is supposed to be a science class, so let's do a science" and uses the entire supply of sodium.

So I wasn't actually in that class when it happened. I was in a classroom directly above the chemistry lab when there's an explosion that I'm sure could have been heard throughout the building. Incidentally, someone had called in a bomb threat a month or two earlier, either as a prank or to get out of exams or whatever. You can probably imagine the chaos in the classroom. Someone pulled the fire alarm and everyone evacuated, but I don't think anyone was actually hurt.

Anyway, there's still a hole in the ceiling tile and they don't do that experiment anymore.

[–] Hamartiogonic@sopuli.xyz 1 points 1 month ago (2 children)

You would also need to improve the thermal efficiency. In a modern fission power plant, about 1/3 of the energy is converted to electricity and 2/3 is just waste heat. Imagine having that sort of efficiency in a chest mounted reactor. Where are you going to dump all that heat?

We need a technological leap that is comparable to the jump from candles to LEDs.

[–] faintwhenfree@lemmus.org 3 points 1 month ago (1 children)

Maybe reactor is based on cold fusion perhaps? So total fiction.

[–] Hamartiogonic@sopuli.xyz 1 points 1 month ago

The arc reactor follows the rule of cool physics. That’s what dictates the, power density, size, shape and color.

[–] Rooster326@programming.dev 1 points 1 month ago (1 children)

Where are you going to dump all that heat?

Into the jets and repulsar beams...?

[–] SpacetimeMachine@lemmy.world 1 points 1 month ago

"Give me one sec cap, I've been standing still for 3 minutes so I have to go blast a hole in something real quick or my suit will explode."

[–] gandalf_der_12te@feddit.org 1 points 1 month ago (1 children)

the idea of picking up a whole power plant and moving it around

funnily enough submarines do that

[–] mojofrododojo@lemmy.world 1 points 1 month ago (1 children)

fusion reactors

no, they don't

[–] gandalf_der_12te@feddit.org 1 points 1 month ago

sry i misread. i read just "nuclear reactor".

[–] DJKJuicy@sh.itjust.works 6 points 1 month ago

Pure fiction. We're a few orders of magnitude off in energy density. And even if we could create that level of energy density, the repulsors and thrusters used for flight and weapons would deplete the energy in minutes.

[–] mcv@lemmy.zip 2 points 1 month ago

Well, his financial power is. But even Elon Musk isn't able to break the laws of physics, no matter how hard he keeps trying.

[–] thebardingreen@lemmy.starlightkel.xyz 2 points 1 month ago

It's completely fictional. It's a fusion reactor the size of a small donut.

[–] skibidi@lemmy.world 2 points 1 month ago

Not achievable with current tech, but there has been more interest in miniature fusion reactors lately.

The generally thinking is that it becomes easier to contain the plasma in smaller formfactors where the field strength is higher - a power plant would then be hundreds of tiny units working in concert rather than one big one. Of course, its fusion so nothing 'real' has come out of it yet, and it is unlikely something man-portable and energy dense enough to power iron man ever will.

[–] AwesomeLowlander@sh.itjust.works 1 points 1 month ago

Simple question - if we could, don't you think we would have?

[–] Tollana1234567@lemmy.today 0 points 1 month ago

SCIFI, it would require something like cold fusion, which is basically a scifi trope. SG1 had a cold fusion episode but with plants, which is even more preposterous. and then another one in SGA, where a race of humans developed controlled "fission/fusion" generators by using a unique mineral form the planet. I believe naquada uses a form of fusion to provide the massive amount of power.