Transport of fast particles in turbulent fields
In light of planned ITER operation, it is important to improve understanding of fast particle behavior. This work focuses on the influence of both electrostatic and electromagnetic background microturbulent fields by studying passive fast ions in gyrokinetic turbulence simulations. Since magnetic fluctuations are the primary source of fast particle diffusion at high energies, the threshold values are investigated where this regime starts to dominate over the effects of electrostatic turbulence. Comparisons with analytical theory are presented.
This paper deals with the development of a mathematical model for very high power density actively shielded air-core superconducting (SC) machines. The interacting forces of SC coils in the actively shielded SC machine are studied using a two-dimensional analytical approach. The transfer relation methodology is employed to analyze the fully air-core SC motor that is designed to reduce the weight of the machine with actively shielded coil stator. Magnetic flux and force density distributions obtained by the proposed method are compared with those obtained from finite element analyses. The results can be considered as elements of a library of tools leading toward efficient optimization and mechanical design of actively shielded SC machines.