Mechanical Scifi Fusion.... Could We Do It?

[Spacescifi]

Scenario: We find a bunch of weird metal ore from a meteorite. Turns out when you magnetize it, it's temperature will stabilize at whatever it is currently when you magnetize it. Meaning attempts to heat it up further don't work. Without magnetization it has the same melting point as iron.

Further tests reveal that somehow, heat conducted or radiated into the magnetized ore is "emitted" back out not as heat.. but as hydrogen gas out of it's outermost layer.

There is an upper limit on how much heat the magnetized ore can take but it's high. Namely the heat of the energy equivalent of it's mass converted into energy. So how much hydrogen gas it produces is equivalent to how much heat in terms of energy is converted into mass. It perfectly converts 100% heat while magnetized into hydrogen gas.

Applications: Could we make a continous fusion  reaction rocket engine out of this scifi metal?

I think maybe. The biggest problems with fusion are containment and keeping the reaction going.

Containment is a solved problem here. The only problem left is keeping the fusion reaction going, can we do it with modern technology?

Or is the best we can do some sort of pulsed fusion rocket?

Secondary application: Spaceship battle armor! Now you no longer need to fear lasers. Because not many will field a laser so powerful it has more energy than your entire magnetized scifi metal hull converted into energy. Certainly nothing we would build today.

Limitations: Ablative heating still works like normal on the magnetized scifi metal. Which means you will still burn up in the atmosphere if you dive too steep on reentry. Particle beams and other kinetic weapons will still heat it like normal if they hit it.

Fusion Engine limitations: Since the magnetized scifi metal can still be heated by kinetic ablation, whatever fusion reaction occuring inside must be made so that it does not particle beam the inner walls of the engine or else it will heat and demagnetize them, killing the the scifi magnetized metal's ability to convert absorbed heat into released hydrogen gas from it's outer layer.

 

Thoughts?

 

Edited August 17, 2023 by Spacescifi

[Nuke]

there is at least one fusion start up using light gas guns to initiate fusion targets via brute force.

[RCgothic]

As a nuclear power plant engineer I didn't continue reading past the fictional material.

But IRL the answer is: no.

Fusion involves getting at least one positively charged nuclei going fast enough that it can overcome electrostatic repulsion and get close enough to another nucleus that the very short ranged nuclear strong force can come into play. Incidentally the reason is easier to use deuterium and tritium for fusion is that they the highest mass to charge ratio of any element and are therefore the easiest to get to collide. Beyond this there are no shortcuts.

[magnemoe]

4 hours ago, Nuke said:

there is at least one fusion start up using light gas guns to initiate fusion targets via brute force.

I know, much more work using magnetic or electrostatic like z-pinch. This is pulsed however. 
But fusing hydrogen is very hard, even for the sun, the sun don't produce that much energy for its size. 

 

[Hannu2]

So, that odd material converts all energy to hydrogen gas at some temperature (less than 1500 C) which metal has when it is activated. I do not see how that would lead fusion any easier than hydrogen gas taken from regular gas cylinder.  You should still give hydrogen atoms huge energy somehow, which is the main problem.

However, your material would be very nice for perpetuum mobile industry. You can cool it to 4 K and activate. After that it would be practically infinite cold sink. Any industrial power would produce just trace amounts on hydrogen which would be easy to ventilate safely away.

[Spacescifi]

1 hour ago, Hannu2 said:

So, that odd material converts all energy to hydrogen gas at some temperature (less than 1500 C) which metal has when it is activated. I do not see how that would lead fusion any easier than hydrogen gas taken from regular gas cylinder.  You should still give hydrogen atoms huge energy somehow, which is the main problem.

However, your material would be very nice for perpetuum mobile industry. You can cool it to 4 K and activate. After that it would be practically infinite cold sink. Any industrial power would produce just trace amounts on hydrogen which would be easy to ventilate safely away.

Thank you!

Originally I designed this concept as a work around explaination for why scifi spaceships never use massive radiator wings (which at the energy levels they would emit would fry oncoming spacecraft nearby anyway unless the wings are massive).

The engine metal does not cause fusion but contains it. My idea was try the fusion torus or some other type of fusion reactor.... made ofvthe scifi metal which won't melt since it's melting point would be way higher than any heat fusion could put out.

We know how to do fusion. The trouble is containment (solved here) and keeping the proceed going.

Which is why I tend to think the easiest fusion rocket would be a pulsed one since you don't havd to sustain the reaction.

[Terwin]

Cost-effective containment is an issue for fusion due to neutron activation, but a much bigger issue for fusion is a cost-effective means of triggering the fusion itself.  

I think it was only a few years ago that they finally got a fusion reaction that produced more energy than it absorbed to initiate.

And this ignores all of the inefficiencies of getting that energy converted and concentrated to where it needed to be(something on the order of a few percent efficient) or the difficulties in extracting that energy in a useful form(possibly as high as 40-50% efficient if we are lucky)

So just getting fusion to the point where it can power itself is still multiple orders of magnitude of efficiency away at least.

The cost of repairing/replacing shielding is still so far in the future that we do not even know for certain it will be an issue.

[Nuke]

7 hours ago, magnemoe said:

I know, much more work using magnetic or electrostatic like z-pinch. This is pulsed however. 
But fusing hydrogen is very hard, even for the sun, the sun don't produce that much energy for its size. 

 

i think they are more about designing the fusion targets. metal disk hits what looks like a block of acrylic with bubbles of deuterium embedded with it. the light gas guns are just the same kind they use for testing asteroid impact models. inertial confinement taken literally. but if they can come up with a geometry that focuses the shockwaves on the fuel bubble just right to cause rapid compression. it sort of seems familiar, this was done to focus explosives onto plutonium cores because reasons, you also see similar in laser weaponization (pulsing to create shockwaves which do more damage than the laser itself). its possibly one of the most interesting "dumb" methods that ive seen.

does compression heating even work once the electrons have been stripped?

1 hour ago, Terwin said:

Cost-effective containment is an issue for fusion due to neutron activation, but a much bigger issue for fusion is a cost-effective means of triggering the fusion itself.  

I think it was only a few years ago that they finally got a fusion reaction that produced more energy than it absorbed to initiate.

And this ignores all of the inefficiencies of getting that energy converted and concentrated to where it needed to be(something on the order of a few percent efficient) or the difficulties in extracting that energy in a useful form(possibly as high as 40-50% efficient if we are lucky)

So just getting fusion to the point where it can power itself is still multiple orders of magnitude of efficiency away at least.

The cost of repairing/replacing shielding is still so far in the future that we do not even know for certain it will be an issue.

the problem with laser methods is the laser part. lasers are really not the most efficient gadget in the lab. even if you have a lot of really big ones. making a power plant by this means might work if you can get lasers north of 90% efficient, and i dont think thats even physically possible. 

Edited August 17, 2023 by Nuke

[Vanamonde]

You put heat in and you get hydrogen out? The conversion factor of energy to matter is extremely high. Your ship would have to have a ridiculously powerful generator just to pump enough heat into the thing to generate significant quantities of hydrogen. You'd be better off replacing the generator with a tank full of pre-made hydrogen. 

[Spacescifi]

19 minutes ago, Vanamonde said:

You put heat in and you get hydrogen out? The conversion factor of energy to matter is extremely high. Your ship would have to have a ridiculously powerful generator just to pump enough heat into the thing to generate significant quantities of hydrogen. You'd be better off replacing the generator with a tank full of pre-made hydrogen. 

 

Hydrogen gas is merely a harmless byproduct of a scifi metal that is answer to where the waste heat goes.

1 hour ago, Nuke said:

i think they are more about designing the fusion targets. metal disk hits what looks like a block of acrylic with bubbles of deuterium embedded with it. the light gas guns are just the same kind they use for testing asteroid impact models. inertial confinement taken literally. but if they can come up with a geometry that focuses the shockwaves on the fuel bubble just right to cause rapid compression. it sort of seems familiar, this was done to focus explosives onto plutonium cores because reasons, you also see similar in laser weaponization (pulsing to create shockwaves which do more damage than the laser itself). its possibly one of the most interesting "dumb" methods that ive seen.

does compression heating even work once the electrons have been stripped?

the problem with laser methods is the laser part. lasers are really not the most efficient gadget in the lab. even if you have a lot of really big ones. making a power plant by this means might work if you can get lasers north of 90% efficient, and i dont think thats even physically possible. 

Once more sounds like it only work well as a pulsed rocket.... since we are not speaking of Orion which does work but is destructive.

[magnemoe]

28 minutes ago, Spacescifi said:

Hydrogen gas is merely a harmless byproduct of a scifi metal that is answer to where the waste heat goes.

Once more sounds like it only work well as a pulsed rocket.... since we are not speaking of Orion which does work but is destructive.

I say almost all fusion engine plans are pulsed so are lots of the fusion reactors. 
In fact almost all engines are pulsed, exception is gas and steam turbines and ramjets. 
Unless your car is an EV its use an detonation engine. 
Orion is not destructive to itself. Rockets are destructive to surrounding see the Starship launch  Orion is more so as it using nukes for power.
 

[Vanamonde]

The purpose is not to generate hydrogen as fusion fuel? Then why are you heating the metal, where is the power coming from, what is the hydrogen for, and what is being fused? 

[Nuke]

4 hours ago, Spacescifi said:

Once more sounds like it only work well as a pulsed rocket.... since we are not speaking of Orion which does work but is destructive.

it would be stupid easy to turn this percussive fusion method into a pulse drive, just replace the vacuum vessel with a magnetic nozzle. then we just need to make a light gas gun go brrrrrrrrrrrrrrrrrrrrrrrrt.

its probibly a lot safer and less destructive than using fission pulse units. you probibly dont even need that much of a shock absorber, the magnetic nozzel would handle that for you.

Edited August 17, 2023 by Nuke

[Spacescifi]

4 hours ago, Nuke said:

it would be stupid easy to turn this percussive fusion method into a pulse drive, just replace the vacuum vessel with a magnetic nozzle. then we just need to make a light gas gun go brrrrrrrrrrrrrrrrrrrrrrrrt.

its probibly a lot safer and less destructive than using fission pulse units. you probibly dont even need that much of a shock absorber, the magnetic nozzel would handle that for you.

 

It's my understanding that just like the pusher plate, you need the magnetic nozzle big enough to cover the rear end from the casaba howitzer plasma spear that is directed at the nozzle.

Or else you will burn the hull fir no good reason.

I am correct?

Edited August 18, 2023 by Spacescifi

[Nuke]

most of that stuff should be plasma, which will be directed out the magnetic tailpipe. perhaps a magnetic mirror. you can probibly just shoot the fuel capsules (they need to be cased in non-magnetic materials) at each other at 45 degree angles so they collide in the middle of the nozzle with net rearward momentum. design it so that the projectile path is aimed at dead space in case something happens and one of the targets doesnt fire. until they collide and turn to plasma they wont even see the nozzle. the guns themselves would be outside of the "combustion chamber" shooting through the lattice work. a bigger problem might be that if there are bits that dont ionize, they might turn into shrapnel and rip up your coils. probibly put a blade-edge non ferous wedge armor in between the coils and the planned epicenter, so that those bits get deflected away harmlessly.

Edited August 18, 2023 by Nuke

[kerbiloid]

20 hours ago, RCgothic said:

As a nuclear power plant engineer I didn't continue reading past the fictional material.

But IRL the answer is: no.

Fusion involves getting at least one positively charged nuclei going fast enough that it can overcome electrostatic repulsion and get close enough to another nucleus that the very short ranged nuclear strong force can come into play. Incidentally the reason is easier to use deuterium and tritium for fusion is that they the highest mass to charge ratio of any element and are therefore the easiest to get to collide. Beyond this there are no shortcuts.

Just take a bigger piston for your engine, and make a D+T fusion diesel machine.

[razark]

You have one object at absolute hot temperature.  You have another at absolute cold temperature.

You've created a situation where you have a near infinite temperature gradient that you can use to extract usable power from, plus a bit of hydrogen that doesn't really matter in the overall picture.

~~handwave~~

Magic power generator that uses magic to create power. 

Just write a damn infinite power source into the situation and don't worry about the details, unless you want a lot of people asking "Why does this work?", with a near infinite chain of magic materials/events to try to explain away the magic.

 

Seriously, you have magic material block.  Heat it up the godsonlyknowhowhot degrees whatever.  Drop it into a pot of water.  Use the resulting steam to power a steam engine, and use that to drive propellers that send ships across the aether.  (Aether doesn't exist?!?  Neither does MagicMaterialNumberWhateverYou'veProposed).

 

 

Magic is magic.  If you're going to use it, don't put too much effort into explaining it.

[Hannu2]

23 hours ago, Spacescifi said:

The engine metal does not cause fusion but contains it. My idea was try the fusion torus or some other type of fusion reactor.... made ofvthe scifi metal which won't melt since it's melting point would be way higher than any heat fusion could put out.

We know how to do fusion. The trouble is containment (solved here) and keeping the proceed going.

I have understood that worst problem is heat loss from plasma. If you put plasma in container with permanently cool walls it cools down and you have to input more energy than you get out.  Energy output goes also through walls. Material which has constant temperature independent on energy flow could not conduct heat.  Such material violates known conservation laws and energy produced in fusion would be lost.

But as you said, such material would be excellent heat sink for all imaginable purposes.

Edited August 18, 2023 by Hannu2

[Shpaget]

15 minutes ago, Hannu2 said:

But as you said, such material would be excellent heat sink for all imaginable purposes.

But that is only one half of conservation of energy violation (magically sidestepped by exhausting hydrogen).

The other half is when this material is warmer than environment. Does it absorb hydrogen in this case? What if there is none available?

[Kerbart]

21 hours ago, Vanamonde said:

You put heat in and you get hydrogen out? The conversion factor of energy to matter is extremely high. Your ship would have to have a ridiculously powerful generator just to pump enough heat into the thing to generate significant quantities of hydrogen. You'd be better off replacing the generator with a tank full of pre-made hydrogen. 

Yeah, most people who see E=mc² are not aware that we're not talking about particles being converted but purely the atomic masses which are fractions of the mass of a single neutron. And that already provides tremendous power — all based on what could easily be dismissed as a rounding error. The amount of energy needed to create even a single hydrogen ion would be quite amazing, let alone quantities needed for substantial propulsion.

 

Edit: the atomic mass of two deuterium atoms is 4.02820; the atomic mass of helium is 4.002602. The difference, 0.02560 or roughly 2.5% of the mass of a hydrogen atom, is what basically powers thermonuclear weapons. Nuclear fusion yields tremendous energies, and you're going to need roughly 40× that to power the magic drive.

Edited August 18, 2023 by Kerbart

[kerbiloid]

13 hours ago, razark said:

You have one object at absolute hot temperature.

https://en.wikipedia.org/wiki/Muspelheim

13 hours ago, razark said:

You have another at absolute cold temperature.

https://en.wikipedia.org/wiki/Hvergelmir

13 hours ago, razark said:

You've created a situation where you have a near infinite temperature gradient

https://en.wikipedia.org/wiki/Ginnungagap

13 hours ago, razark said:

that you can use to extract usable power from

https://en.wikipedia.org/wiki/Ymir

13 hours ago, razark said:

Magic power generator that uses magic to create power. 

https://en.wikipedia.org/wiki/Auðumbla

13 hours ago, razark said:

Just write a damn infinite power source into the situation and don't worry about the details, unless you want a lot of people asking "Why does this work?", with a near infinite chain of magic materials/events to try to explain away the magic.

https://en.wikipedia.org/wiki/Búri

13 hours ago, razark said:

Seriously, you have magic material block.  Heat it up the godsonlyknowhowhot degrees whatever.  Drop it into a pot of water.  Use the resulting steam to power a steam engine,

https://en.wikipedia.org/wiki/Niflheim

13 hours ago, razark said:

and use that to drive propellers that send ships across the aether. 

https://en.wikipedia.org/wiki/Naglfar

13 hours ago, razark said:

Magic is magic.  If you're going to use it, don't put too much effort into explaining it.

https://en.wikipedia.org/wiki/Seiðr

***

This worked in the past, why shouldn't in the future?