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Post by The Astronomer on Jun 3, 2017 9:17:26 GMT
2. How do you generate energy from neutron radiation and gamma rays? The thermal energy gained from this reaction is pathetic.
3. Are you going to haul Lithium-7, convert them into Tritium slowly, then use them as fuel instantly?
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Post by RiftandRend on Jun 3, 2017 9:31:33 GMT
2. How do you generate energy from neutron radiation and gamma rays? The thermal energy gained from this reaction is pathetic. 3.5 MeV is nothing to scoff at. If I am not mistaken, D+ 3He Fusion is about 16 times harder to achieve than D+T fusion leading to a lower net energy. |
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Post by RiftandRend on Jun 3, 2017 9:35:44 GMT
3. Are you going to haul Lithium-7, convert them into Tritium slowly, then use them as fuel instantly? n+ 7Li fusion produces an additional neutron, leading to another possible fusion event. Additionally, other sources of neutrons are available, such as fission reactors. But this is beside the point. Fuel availability is a trivial issue for D+T fusion compared to D+ 3He fusion. |
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Post by The Astronomer on Jun 3, 2017 9:41:24 GMT
'Several drawbacks are commonly attributed to D-T fusion power:
1. It produces substantial amounts of neutrons that result in the neutron activation of the reactor materials.
2. Only about 20% of the fusion energy yield appears in the form of charged particles with the remainder carried off by neutrons, which limits the extent to which direct energy conversion techniques might be applied.
3. It requires the handling of the radioisotope tritium. Similar to hydrogen, tritium is difficult to contain and may leak from reactors in some quantity. Some estimates suggest that this would represent a fairly large environmental release of radioactivity.' - Wikipedia
Neutron Radiation Apocalypse! Run!
Btw, do you think CDE should model the neutron activation?
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Post by RiftandRend on Jun 3, 2017 9:52:13 GMT
'Several drawbacks are commonly attributed to D-T fusion power: 1. It produces substantial amounts of neutrons that result in the neutron activation of the reactor materials. 2. Only about 20% of the fusion energy yield appears in the form of charged particles with the remainder carried off by neutrons, which limits the extent to which direct energy conversion techniques might be applied. 3. It requires the handling of the radioisotope tritium. Similar to hydrogen, tritium is difficult to contain and may leak from reactors in some quantity. Some estimates suggest that this would represent a fairly large environmental release of radioactivity.' - Wikipedia NEUTRON RADIATION APOCALYPSE, YOU D+T FUSION-ER! HAHAHA! (lol) Flawed it may be, D+T fusion is far more practical than D+ 3He fusion. You would need to process 100 million tons of lunar soil (the location with the highest ppm in the solar system known so far, though mercury may be better) to acquire 1 ton of 3He. To power the world, 902,985,074,626 tons of lunar soil would have to be processed yearly assuming 100% energy efficiency and 100% reclamation efficiency. |
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Post by The Astronomer on Jun 3, 2017 9:53:59 GMT
'Several drawbacks are commonly attributed to D-T fusion power: 1. It produces substantial amounts of neutrons that result in the neutron activation of the reactor materials. 2. Only about 20% of the fusion energy yield appears in the form of charged particles with the remainder carried off by neutrons, which limits the extent to which direct energy conversion techniques might be applied. 3. It requires the handling of the radioisotope tritium. Similar to hydrogen, tritium is difficult to contain and may leak from reactors in some quantity. Some estimates suggest that this would represent a fairly large environmental release of radioactivity.' - Wikipedia NEUTRON RADIATION APOCALYPSE, YOU D+T FUSION-ER! HAHAHA! (lol) Flawed it may be, D+T fusion is far more practical than D+ 3He fusion. You would need to process 100 million tons of lunar soil (the location with the highest ppm in the solar system known so far, though mercury may be better) to acquire 1 ton of 3He. To power the world, 902,985,074,626 tons of lunar soil would have to be processed yearly assuming 100% energy efficiency and 100% reclamation efficiency. 902,985,074,626 tons of lunar soil every year? Every century? Well, lithium is running out, so I guess it's not much better anyways. Let's stop this argument with this link. |
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Post by RiftandRend on Jun 3, 2017 10:11:40 GMT
Flawed it may be, D+T fusion is far more practical than D+ 3He fusion. You would need to process 100 million tons of lunar soil (the location with the highest ppm in the solar system known so far, though mercury may be better) to acquire 1 ton of 3He. To power the world, 902,985,074,626 tons of lunar soil would have to be processed yearly assuming 100% energy efficiency and 100% reclamation efficiency. 902,985,074,626 tons of lunar soil every year? Every century? Well, lithium is running out, so I guess it's not much better anyways. Let's stop this argument with this link. Why stop now? we've already polluted the last 2 pages with offtopic discussion so why not the next few dozen  The D+D fusion required to breed 3He is about twice as difficult as D+ 3He fusion and may have a net energy negative with modern technology. The other 2 reactions are almost certainly energy negative. As to the somewhat absurd soil processing requirement, the world has a yearly power consumption of ~150,000 TWh, and assuming ~6 tons of 3He per TWh and 100,000,000 tons of lunar soil per ton of 3He you get... 90 trillion tons of lunar soil yearly, quite a bit higher than my previous estimate. |
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Post by The Astronomer on Jun 3, 2017 10:18:59 GMT
902,985,074,626 tons of lunar soil every year? Every century? Well, lithium is running out, so I guess it's not much better anyways. Let's stop this argument with this link. Why stop now? we've already polluted the last 2 pages with offtopic discussion so why not the next few dozen The D+D fusion required to breed 3He is about twice as difficult as D+ 3He fusion and may have a net energy negative with modern technology. Anyways, how to stop the neutron activation, then? |
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Post by RiftandRend on Jun 3, 2017 10:23:11 GMT
Why stop now? we've already polluted the last 2 pages with offtopic discussion so why not the next few dozen The D+D fusion required to breed 3He is about twice as difficult as D+ 3He fusion and may have a net energy negative with modern technology. Anyways, how to stop the neutron activation, then? Neutron activation is a big issue, but highly modular reactor walling filled with lithium would probably handle it. Once a tile has expired, it would be removed and the fused tritium extracted. Also, I updated my previous post. Edit: another issue with the 3He breeder, 3He has a large neutron cross section, so you may loose a significant fraction of the produced 3He to n+ 3He fusion. |
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Post by The Astronomer on Jun 3, 2017 10:26:33 GMT
TOO LAZY.Anyways, how to stop the neutron activation, then? Neutron activation is a big issue, but highly modular reactor walling filled with lithium would probably handle it. Once a tile has expired, it would be removed and the fused tritium extracted. Also, I updated my previous post. Above: "Quite a bit higher" No, that's not 'quite a bit', that's 1000 times more. Here: So, you combined radiation shielding with tritium breeding? Btw: Uranus covfefe gas mining is promising. |
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Post by randommechanicumguy on Jun 3, 2017 15:44:50 GMT
i'm caring less about what type of fusion is the best, and rather how to implement it in the actual game
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Post by Kerr on Jun 3, 2017 16:42:31 GMT
Can't He³ be harvested on all gas giants? e.g Uranus, Jupiter, saturn.
p+B11: AN+, 70TJ/kg, 4,5% c Vmax. Pro: Aneutronic and mainly/only helium ions. Con: Needs 500x LC.)
D+T: AN+, 340TJ, 8,7% c Vmax. Pro: Easy to ignite and quite abundant. Con: 80% of the KE is wasted in Neutrons (1x LC.)
D+He³: AN+, 353TJ, 8,9% c Vmax. Pro: Roughly 4x times for efficient than D-T fusion Con: Rare. (16x LC.)
p+p+p+p: AN-, 650TJ, 11,7% c Vmax. Pro: Very high energy density Con: huge Lawson Criterion. (>500x)
LC: Lawson Criterion: How hard is to start and maintain the fusion.
AN: If Aneutronic.
Conclusion: p+B11 and D+He³ are the best candidates for fusion drives, p+B11 Needs very high amount energy to be ignited while only producing relatively low amounts, D+He³ is hard to get in masses.
D-T fusion can be utilised in some kind of Orion/Medusa/etc. design where directed particles are not needed but instead catched/ used to heat a propellant mass, they won't reach the same efficiencies as Aneutronic fusion drives but they will shine in terms of simplicity and cost effectiveness.
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Post by Kerr on Jun 3, 2017 17:09:47 GMT
The AstronomerCould you add a pseudo-tripropellant fusion? Antimatter + D-He³? Amat price would be around 1kg/1Gc, with a fuel ratio of 1mg/100kg for D-He³ fusion. That means you need 1Mc Amat for every 100t of fusion fuel. You can increase this value by 16x if you want to, because the 1mg/100kg is for Li²DT fuel and not for D-He³.
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Post by The Astronomer on Jun 3, 2017 17:14:02 GMT
The Astronomer Could you add a pseudo-tripropellant fusion? Antimatter + D-He³? Amat price would be around 1kg/1Gc, with a fuel ratio of 1mg/100kg for D-He³ fusion. That means you need 1Mc Amat for every 100t of fusion fuel. You can increase this value by 16x if you want to, because the 1mg/100kg is for Li²DT fuel and not for D-He³. I think you'll want to mix Deuterium and Helium-3 together, combining them with amat. It'd be really tough. |
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Post by Enderminion on Jun 3, 2017 17:19:59 GMT
antimatter catalyzed fusion?
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