Fusion doesn't take place in the outer layers of the Sun. Only in the core, and you can't duplicate the conditions and confinement there.
I knew that fusion doesn't take place in the corona but I also know that you can find plasma from 1MK to 20MK there, and it's actually a scientific question how it reaches similar temperatures at such a great distance from the center, especially since there is a lower layer as cold as 4100K.
Plasma can't be stored.
What if the reactor is contained in the probe? So the reaction is started during solar flyby then continues on it's own as it should? The small tokamak inside the probe could initially contain only high density but cold tritium and deuterium that would be ignited by the injection of 20MK plasma. Then the reaction would continue. The magnetic field in the Tokamak would be activated only after the reaction has started.
Quote from: Jorge on 05/22/2010 05:41 pmThe act of confining the plasma (by whatever method) will take enough energy out that it won't be plasma any more.Learn about the second law of thermodynamics to find out why this won't work. Entropy always beats you. You can't win, you can't break even, you can't leave the game.What if the reactor is contained in the probe? So the reaction is started during solar flyby then continues on it's own as it should? The small tokamak inside the probe could initially contain only high density but cold tritium and deuterium that would be ignited by the injection of 20MK plasma. Then the reaction would continue. The magnetic field in the Tokamak would be activated only after the reaction has started.
The act of confining the plasma (by whatever method) will take enough energy out that it won't be plasma any more.Learn about the second law of thermodynamics to find out why this won't work. Entropy always beats you. You can't win, you can't break even, you can't leave the game.
Quote from: cosmicpax on 05/22/2010 06:05 pmWhat if the reactor is contained in the probe? So the reaction is started during solar flyby then continues on it's own as it should? The small tokamak inside the probe could initially contain only high density but cold tritium and deuterium that would be ignited by the injection of 20MK plasma. Then the reaction would continue. The magnetic field in the Tokamak would be activated only after the reaction has started.No, it doesn't work that way. You really need to learn a bit of fusion physics before getting into this sort of discussion.The density in the corona is too low. The energy available from coronal plasma particles is too low. And how, pray tell, are you going to ignite a plasma without the magnetic field turned on? I can only conclude that you have no idea what the magnetic field is for...
chain reaction
superconducting magnets require so much energy
How does this help anything versus just collecting the gas using a fusion reactor on your main spacecraft?
it's not something you can grow from a small 'spark' like with fission.
"the stability of spheromak plasmas also allows their creation by 'gun' devices. In a plasma gun, a pulse of electricity ionizes some gas, which is expelled from the barrel and coalesces into a stable spheromak."
I believed a similar process could work with 20MK plasma from the corona but I'm wrong.
Also, I don't believe the bulk of the corona is quite that hot. Wikipedia says 1-3 MK, not 20.
"The low corona, which is very near the surface of the Sun, has a particle density around 1015–1016 m−3.
The average temperature of the corona and solar wind is about 1 million–2 million kelvins, however, in the hottest regions it is 8 million–20 million kelvins.[54] "I can't access the paper on reference 54 anyway so I can't be more precise.
Quote from: kfsorensen on 05/22/2010 04:58 pmFusion doesn't take place in the outer layers of the Sun. Only in the core, and you can't duplicate the conditions and confinement there.I knew that fusion doesn't take place in the corona but I also know that you can find plasma from 1MK to 20MK there, and it's actually a scientific question how it reaches similar temperatures at such a great distance from the center, especially since there is a lower layer as cold as 4100K.