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Post by The Astronomer on Jun 9, 2017 12:02:30 GMT
That is assuming any reasonable fraction of it is absorbed. Typically it takes a fair bit of material to absorb high energy gamma rays... Sorry to tell you, but I excluded Gamma-rays from my calculations for that exact reason. Nvm. My newest fusion reaction update excluded gamma rays for that exact reason.
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Post by Kerr on Jun 9, 2017 12:06:51 GMT
Sorry to tell you, but I excluded Gamma-rays from my calculations for that exact reason. Nvm. My newest fusion reaction update excluded gamma rays for that exact reason. Is your new fusion reaction update already online?
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Post by matttheczar on Jun 9, 2017 12:29:05 GMT
My hope is that electrostatic confinement (polywell) fusion works, since it seems a great deal cheaper than the other options so far.
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Post by Kerr on Jun 9, 2017 12:49:27 GMT
My hope is that electrostatic confinement (polywell) fusion works, since it seems a great deal cheaper than the other options so far. What about Z-Pinch fusion? It is a pretty solid candidate. Currently figuring out some numbers for a D-He³ Firefly starship.
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Post by The Astronomer on Jun 9, 2017 13:34:33 GMT
Nvm. My newest fusion reaction update excluded gamma rays for that exact reason. Is your new fusion reaction update already online? Not yet. However, it is a complete overhaul. For example, both D + T and D + He-3 reactions now used the same Deuterium material.
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Post by Kerr on Jun 9, 2017 13:46:09 GMT
Is your new fusion reaction update already online? Not yet. However, it is a complete overhaul. For example, both D + T and D + He-3 reactions now used the same Deuterium material. Very nice, I wondered what you think is the most promising fusion fuel?
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Post by The Astronomer on Jun 9, 2017 13:52:57 GMT
Not yet. However, it is a complete overhaul. For example, both D + T and D + He-3 reactions now used the same Deuterium material. Very nice, I wondered what you think is the most promising fusion fuel? D + He-3, why? Just add antihydrogen. That is, I still don't understand why most people seem tho choose proton + Boron-11.
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Post by Kerr on Jun 9, 2017 14:17:00 GMT
Very nice, I wondered what you think is the most promising fusion fuel? D + He-3, why? Just add antihydrogen. That is, I still don't understand why most people seem tho choose proton + Boron-11. Yup, Considering that the Icarus Firefly starship uses Z-pinched DD Fusion, which produces nearly 3-4x more heat, needs 1,5x more energy to be initiated, and has only a third of the energy density. D-He³ and its x-ray doesn't seem to be that much of an problem. Just let D-He³ neutrons & x-rays radiate into the voids of space instead into the engine bell. And Helium-3 mining isn't that hard, for Project Daedalus a few balloons could generate sufficient Helium-3 for 50kT D-He³ in just 20 years. With 100x of these balloon you can generate enough helium-3 for 2,1kT D-He³ in just one month. proton-Boron doesn't have many advantages, 70TJ/kg can be directly converted into thrust power. D-He³ 25% goes into neutrons and x-rays, on other side it has 350TJ/kg, 5x more energy per kg. 70 vs. 260 TJ. Maybe most people clicked on it because it had "Boron" in it? To be more serious, I don't really know why.
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Post by The Astronomer on Jun 9, 2017 14:18:48 GMT
D + He-3, why? Just add antihydrogen. That is, I still don't understand why most people seem tho choose proton + Boron-11. Yup, Considering that the Icarus Firefly starship uses Z-pinched DD Fusion, which produces nearly 3-4x more heat, needs 1,5x more energy to be initiated, and has only a third of the energy density. D-He³ and its x-ray doesn't seem to be that much of an problem. Just let D-He³ neutrons & x-rays radiate into the voids of space instead into the engine bell. And Helium-3 mining isn't that hard, for Project Daedalus a few balloons could generate sufficient Helium-3 for 50kT D-He³ in just 20 years. With 100x of these balloon you can generate enough helium-3 for 2,1kT D-He³ in just one month. proton-Boron doesn't have many advantages, 70TJ/kg can be directly converted into thrust power. D-He³ 25% goes into neutrons and x-rays, on other side it has 350TJ/kg, 5x more energy per kg. 70 vs. 260 TJ. Maybe most people clicked on it because it had "Boron" in it? To be more serious, I don't really know why. I really need to make a new poll, with stats instead of names. acrosome literally chose proton + Boron-11 because of boron itself. Kerr No, you can't.
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Post by Kerr on Jun 9, 2017 14:21:06 GMT
Yup, Considering that the Icarus Firefly starship uses Z-pinched DD Fusion, which produces nearly 3-4x more heat, needs 1,5x more energy to be initiated, and has only a third of the energy density. D-He³ and its x-ray doesn't seem to be that much of an problem. Just let D-He³ neutrons & x-rays radiate into the voids of space instead into the engine bell. And Helium-3 mining isn't that hard, for Project Daedalus a few balloons could generate sufficient Helium-3 for 50kT D-He³ in just 20 years. With 100x of these balloon you can generate enough helium-3 for 2,1kT D-He³ in just one month. proton-Boron doesn't have many advantages, 70TJ/kg can be directly converted into thrust power. D-He³ 25% goes into neutrons and x-rays, on other side it has 350TJ/kg, 5x more energy per kg. 70 vs. 260 TJ. Maybe most people clicked on it because it had "Boron" in it? To be more serious, I don't really know why. I really need to make a new poll, with stats instead of names. acrosome literally chose proton + Boron-11 because of boron itself. Can a post have two polls? Wanted to make an "best way to ignite fusion poll". With Polywell, Antimatter, Z-pinch, Inertial Confinement (Lasers/Particle beams) The Astronomer Alright, then I gonna make an extra poll for them.
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Post by apophys on Jun 9, 2017 15:46:13 GMT
proton-Boron doesn't have many advantages, 70TJ/kg can be directly converted into thrust power. D-He³ 25% goes into neutrons and x-rays, on other side it has 350TJ/kg, 5x more energy per kg. 70 vs. 260 TJ. Maybe most people clicked on it because it had "Boron" in it? To be more serious, I don't really know why. You mentioned that p+B has an inherent advantage of being able to use its potential exhaust velocity more fully. Which imho would be a pretty significant advantage. p+B has other points: boranes are nicely dense as propellant, and work fine in NTRs and chem thrusters as well can be one single propellant instead of two high-temperature propellant no need for free hydrogen/helium which can leak out of its container much less rad shielding needed no neutron embrittlement inducing radioactivity really cheapB-11 is depleted boron, a byproduct from refining B-10, which is the magical neutron-absorbing boron we all know and love for our control rods For confinement, there's also magneto-inertial, and cusp confinement.
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Post by Kerr on Jun 9, 2017 16:04:45 GMT
proton-Boron doesn't have many advantages, 70TJ/kg can be directly converted into thrust power. D-He³ 25% goes into neutrons and x-rays, on other side it has 350TJ/kg, 5x more energy per kg. 70 vs. 260 TJ. Maybe most people clicked on it because it had "Boron" in it? To be more serious, I don't really know why. You mentioned that p+B has an inherent advantage of being able to use its potential exhaust velocity more fully. Which imho would be a pretty significant advantage. p+B has other points: boranes are nicely dense as propellant, and work fine in NTRs and chem thrusters as well can be one single propellant instead of two high-temperature propellant no need for free hydrogen/helium which can leak out of its container much less rad shielding needed really cheapB-11 is depleted boron, a byproduct from refining B-10, which is the magical neutron-absorbing boron we all know and love for our control rods For confinement, there's also magneto-inertial, and cusp confinement. The potential exhaust velocity is debunked, after reading my bible (Atomic Rockets) I looked over the Firefly ship, which uses DD Fusion, which has even more radiation than D-He³, 3,2x more in fact. D-He³ Can very well reach +20Mm/s velocities using no engine bell but an open system were most radiation can escape into space. The rest amount of radiation will be radiated using radiators. Compared to D-He³ the needed amount of rad-shielding is negligible, distance shielding is more than enough to protect yourself from these 5% Neutrons, and p+B11 also has heat problems. Probably even more than D-He³, 25-33% of the energy might radiated as x-rays on your p+B11 Engine. Considering that 25% of energy is lost when at temperatures from 250-300 kev (26,7Mm/s exhaust velocity). 300 kev is the minimum temperature where boron fusion can even happen (for comparison D-He³ starts at 30 kev, and D-T at 5.2kev). At last, D-He³ carries 3,8x more energy than p-B11, p-B11 can barely reach interstellar velocities without enourmous mass ratios <10:1.
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Post by Kerr on Jun 9, 2017 16:50:56 GMT
Also, How fast do you guys think would a fusion ship travel through a star system? The Astronomer
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Post by thorneel on Jun 9, 2017 21:19:42 GMT
boranes are nicely dense as propellant, and work fine in NTRs and chem thrusters as well can be one single propellant instead of two high-temperature propellant no need for free hydrogen/helium which can leak out of its container much less rad shielding needed no neutron embrittlement inducing radioactivity really cheapPretty much my reasons. Nearly no neutron and availability of the stuff are the two biggest to me.
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Post by The Astronomer on Jun 10, 2017 3:25:47 GMT
Also, How fast do you guys think would a fusion ship travel through a star system? The Astronomer Well, a few hundred kilometers per second for normal trips, can went up to thousands of kilometers per second if the two objects are really far apart and the ship has a lot of delta-v.
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