3 ms·
That's pretty much what's happening here, fusion output increases with the fourth power of the magnetic field. Double the field, 16X the output. But if we take
by DennisP 6y ago
That's pretty much what's happening here, fusion output increases with the fourth power of the magnetic field. Double the field, 16X the output. But if we take it much further, we'll reach a point where the limit is the structural strength of the reactor.
A few years ago I got to tour MIT's Alcator C-Mod, which had the most powerful field of any tokamak to date. A grad student showed us a metal tie rod, about a meter long, and said they'd calculated that two of them could hold down the Space Shuttle while it was trying to launch. To hold the reactor together while it was operating took 38 of those.
- pfdietz 6y agoThe peak on-coil magnetic field in the ARC design (from the 2014 paper) is 23 Tesla. The pressure of a 23 T magnetic field is 2100 bar, nearly twice the pressure at the bottom of the Marianas trench, and comparable to the chamber pressure of a handgun. 60% of the mass of their design was the stainless steel structure needed to support the magnets against the outward JxB forces. Fusion's prospects would likely be helped some by plasma configurations with much higher beta than tokamaks. At least the experiments would be cheaper.