4 ms·

As with every fusion article, I encourage anyone interested in the space to look into General Fusion. They're using liquid metal as both the reaction vessel and

As with every fusion article, I encourage anyone interested in the space to look into General Fusion. They're using liquid metal as both the reaction vessel and as a means to extract power. Really cool stuff.

ncmncm 5y ago
This actually looks like it could be practical. Important differences from the Tokamak concept are: 1. No enormous magnets 2. No exposure of fragile equipment to hot neutrons 3. The reaction occurs in a bubble inside molten lead/lithium, compressed mechanically. 4. None of the pipes carrying hot metal (or anything else) are exposed to hot neutrons, so need not be replaced frequently. 5. The amount of molten metal is relatively small -- not thousands of tons, but just tons (much of it lead, why?) Similarities are that the fusion energy is carried by kinetic neutrons absorbed in molten metal, and extracted by heat-exchange with another fluid, thence to steam; and the molten metal is processed continuously or periodically to extract tritium, which will serve as more fuel. Big question is if the reaction rate is high enough. It seems to depend on how much plasma can be packed into the bubble before it is compressed, and how long you have to keep it compressed before releasing and exhausting the synthetic helium. It seems like if there is any tritium left over afterward, you would want to cool and reclaim that. You get one hot neutron out per tritium in, which in a Li6/Li7 mixture might breed [0] two tritium out, plus some helium. With lead mixed in, wouldn't it steal slow neutrons you need to get above parity? I guess as long as the lead doesn't steal too many, it is OK? But what is the lead for? [0] http://hyperphysics.phy-astr.gsu.edu/hbase/NucEne/fusion.html http://hyperphysics.phy-astr.gsu.edu/hbase/NucEne/fusion.htm...
- ncmncm 5y ago
  Guessing the lead is so the ball of molten metal to make the bubble in can be not so big as to be impractical to handle.

ncmncm 5y ago

This actually looks like it could be practical. Important differences from the Tokamak concept are: 1. No enormous magnets 2. No exposure of fragile equipment to hot neutrons 3. The reaction occurs in a bubble inside molten lead/lithium, compressed mechanically. 4. None of the pipes carrying hot metal (or anything else) are exposed to hot neutrons, so need not be replaced frequently. 5. The amount of molten metal is relatively small -- not thousands of tons, but just tons (much of it lead, why?) Similarities are that the fusion energy is carried by kinetic neutrons absorbed in molten metal, and extracted by heat-exchange with another fluid, thence to steam; and the molten metal is processed continuously or periodically to extract tritium, which will serve as more fuel. Big question is if the reaction rate is high enough. It seems to depend on how much plasma can be packed into the bubble before it is compressed, and how long you have to keep it compressed before releasing and exhausting the synthetic helium. It seems like if there is any tritium left over afterward, you would want to cool and reclaim that. You get one hot neutron out per tritium in, which in a Li6/Li7 mixture might breed [0] two tritium out, plus some helium. With lead mixed in, wouldn't it steal slow neutrons you need to get above parity? I guess as long as the lead doesn't steal too many, it is OK? But what is the lead for? [0] http://hyperphysics.phy-astr.gsu.edu/hbase/NucEne/fusion.html http://hyperphysics.phy-astr.gsu.edu/hbase/NucEne/fusion.htm...

ncmncm 5y ago
Guessing the lead is so the ball of molten metal to make the bubble in can be not so big as to be impractical to handle.