Runs of the NSTAB equilibrium and stability code show there are many 3D solutions of the advanced tokamak problem subject to axially symmetric boundary conditions. These numerical simulations based on mathematical equations in conservation form predict that the ITER project will encounter pervasive disruptions and ELMs crashes. Test particle runs of the TRAN Monte Carlo code suggest that for quasineutrality to prevail in tokamaks a certain minimum level of 3D asymmetry of the magnetic spectrum is required which is comparable to that found in quasiaxially symmetric (QAS) stellarators. The computational theory suggests that a QAS stellarator with two field periods and proportions like those of ITER is a good candidate for a fusion reactor. For DEMO we propose an experiment that combines the best features of ITER with a system of QAS coils providing external rotational transform. We have discovered a configuration with unusually good quasisymmetry that is ideal for this task.
Citation: Journal of Research (NIST JRES) -
NIST Pub Series: Journal of Research (NIST JRES)
Pub Type: NIST Pubs
magnetic fusion, plasma physics, computational science