Collisionless charged particle motion in torsatrons is studied with the use of a longitudinal adiabatic invariant and numerical integration of the guiding centre drift equations. Emphasis is placed on investigating the influence of satellite harmonics of the helical magnetic field and the radial electric field on particle confinement. From this standpoint, the particle orbits, the limiting cycles of equations of particle motion, and the shape and size of regions in phase space in which the particle orbits lie are considered as a function of the device parameters. A comparison is made of magnetic configurations of various types differing in the number of helical field periods, in the inhomogeneity ratio t/l and in their sets of satellite harmonics. The characteristics of the configurations compared are close to the parameters of actual torsatrons: Heliotron E, ATF and Uragan-2M
A code to solve the Vlasov–Fokker–Planck equation applied to particle transport in magnetic turbulence