| Summary: | BackgroundTokamak is a possible implementation of controlled nuclear fusion whilst the particle transportation plays an important role in maintaining the progress of nuclear fusion reactions.PurposeThis study aims to investigate the effects of ripple field and neoclassical tearing mode (NTM) on the migration of deuterium ions in Tokamak by numerical simulation. and provide a reference for the confinement of high energy particles.MethodsThe guiding center orbit code ORBIT was employed for numerical simulation. Effects of NTM and ripple field on particles with different positions, pitch angles and energies, were studied in details.Results & ConclusionsSimulation results show that the particle loss rate is high under the condition of high magnetic surface and low pitch angle. NTM mainly causes the loss of passing particles, while the loss of trapped particles is mainly caused by ripple field. When both perturbations are considered, the loss of particles is approximately the sum of losses by two perturbations acting alone. Ripple field will significantly increase toroidal angular momentum diffusion of trapped particles without affecting the passing particles, whilst NTM mainly influences toroidal angular momentum diffusion of passing particles. The particle loss situation basically keeps the original characteristics regardless of NTM frequency varition, while the momentum diffusion condition of particle loss changes with the increase of NTM frequency.
|
|---|