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Post by samchiu2000 on Mar 22, 2017 23:35:30 GMT
Why the critical mass of fissile material is not considered in nuclear bomb and reactor design?
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Post by kaiserwilhelm on Mar 23, 2017 17:01:29 GMT
Heretic leave my mini nukes/reactors alone.
But seriously though it has to be an overlocked thing since as far as I am aware neutron reflectors don't do anything besides liminting radiation leakages
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Post by concretedonkey on Mar 24, 2017 6:51:26 GMT
mmm from what I understand this is not exactly so. It should reflect neutrons back and directly influence the core - turn a subcritical mass in to critical... and it seems wiki agrees : link Keep in mind that my knowledge in the issue is strictly superficial.
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Post by dragonkid11 on Mar 24, 2017 7:19:01 GMT
Nuclear reaction is started by sufficient density of neutrons flying everywhere.
Get enough critical mass, and you get enough neutrons.
Neutron reflector instead reflect the neutron back to the fissile material, so even with less critical mass, you can still have a nuclear bomb, or a working nuclear reactor.
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Post by samchiu2000 on Mar 24, 2017 7:56:29 GMT
Nuclear reaction is started by sufficient density of neutrons flying everywhere. Get enough critical mass, and you get enough neutrons. Neutron reflector instead reflect the neutron back to the fissile material, so even with less critical mass, you can still have a nuclear bomb, or a working nuclear reactor. Sound a good explain but why the smallest nuke IRL is order of magnitudes heavier than the one in COADE?
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Post by bigbombr on Mar 24, 2017 8:12:00 GMT
Nuclear reaction is started by sufficient density of neutrons flying everywhere. Get enough critical mass, and you get enough neutrons. Neutron reflector instead reflect the neutron back to the fissile material, so even with less critical mass, you can still have a nuclear bomb, or a working nuclear reactor. Sound a good explain but why the smallest nuke IRL is order of magnitudes heavier than the one in COADE? What's the highest refinement ever used IRL? In CoaDE, it's 97%.
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Post by dragonkid11 on Mar 24, 2017 10:20:15 GMT
Nuclear reaction is started by sufficient density of neutrons flying everywhere. Get enough critical mass, and you get enough neutrons. Neutron reflector instead reflect the neutron back to the fissile material, so even with less critical mass, you can still have a nuclear bomb, or a working nuclear reactor. Sound a good explain but why the smallest nuke IRL is order of magnitudes heavier than the one in COADE? Because nobody sane is making holy hand grenade in real life. And the cost of fissile material prohibit development of mini nuke. And most country want the biggest bang out of their nuke etc etc. Seriously, this question is kinda self explanatory. Look at what we have been doing in CoaDE and look at how we just want to miniaturize everything. Nobody in real life want to make super small nuke because they are expensive and not really useful. We makes it because it attracts our attention and want for mininuke.
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Post by shiolle on Mar 24, 2017 10:33:46 GMT
When I first saw nuclear hand grenades, I thought there is some integration error at the lower end of critical material mass. However when I started reading about small nukes I noticed one thing: yield isn't something constant, and as the amount of fissile material drops it seems as if the probability of a fizzle goes up. This is how I understand it:
At certain mass, fissile material will start a chain reaction on it's own, triggered by natural radioactive decay. The more you reduce the amount of radioactive material, the more you need to compress it in order to achieve criticality. To compress it you need to apply a certain amount of pressure which is what explosive lenses are for. But as you scale down your nuclear device, the amount of explosives scales down too. When you reduce your mass of fissile material by the factor of eight, you reduce its radius by the factor of two and area by the factor of four. If the mass of your explosives scales accordingly you now have a thinner layer of explosives around the core and your pressure is suddenly dropping dramatically. In other words, your ratio of explosives to fissile materials is going to shoot through the roof as you try to scale the amount of fissile materials down, and we are not really seeing this in the game. Additionally, neutron reflector gets thinner too, shouldn't its effectiveness drop?
So I believe there are limitations that cannot be solved just by better arrangement of charges, plus as the amount of explosives is reduced the randomness of resulting yield will increase until finally the device will always fizzle or the amount of force of the conventional explosion overshadows any nuclear effects. At the hand-grenade level you should have a dirty bomb.
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Post by Easy on Mar 24, 2017 13:20:42 GMT
Nuclear reaction is started by sufficient density of neutrons flying everywhere. Get enough critical mass, and you get enough neutrons. Neutron reflector instead reflect the neutron back to the fissile material, so even with less critical mass, you can still have a nuclear bomb, or a working nuclear reactor. CoDE lets you build reactors below critical mass without any neutron reflector mass. So that doesn't answer the problem.
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Post by samchiu2000 on Mar 24, 2017 13:23:24 GMT
Nuclear reaction is started by sufficient density of neutrons flying everywhere. Get enough critical mass, and you get enough neutrons. Neutron reflector instead reflect the neutron back to the fissile material, so even with less critical mass, you can still have a nuclear bomb, or a working nuclear reactor. CoDE lets you build reactors below critical mass without any neutron reflector mass. So that doesn't answer the problem. Yea i just find this problem when messing up with the design...
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Post by newageofpower on Mar 24, 2017 14:34:03 GMT
Sound a good explain but why the smallest nuke IRL is order of magnitudes heavier than the one in COADE? What's the highest refinement ever used IRL? In CoaDE, it's 97%. Enrichments of 99% have been obtained before, but it was considered economically prohibitive for anything other than lab work.
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Post by The Astronomer on Mar 24, 2017 15:26:45 GMT
Try using antiprotons on them. Might work.
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Post by nerd1000 on Mar 25, 2017 12:00:49 GMT
Try using antiprotons on them. Might work. The solution is Antimatter! Antimatter fixes everything!
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ndeo
Junior Member
It's not a flashlight... It's a High-frequency relativistic boson cannon
Posts: 67
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Post by ndeo on Mar 25, 2017 13:37:55 GMT
Try using antiprotons on them. Might work. The solution is Antimatter! Antimatter fixes everything! How about metastable Neutronium? ...What do yah mean that's impossible?
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Post by The Astronomer on Mar 25, 2017 13:58:21 GMT
The solution is Antimatter! Antimatter fixes everything! How about metastable Neutronium? ...What do yah mean that's impossible? Have fun trying to synthesize them.
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