Year: 2015
Type: dissertation
Abstract: When designing a fusion device, knowledge of the particle motion inside the fusion plasma is crucial. The charged plasma particles are confined inside the device using\na strong magnetic field, which influences particle motion. Particle trajectories can therefore be obtained by numerically solving the equations of motion for a charged\nparticle in the confining magnetic field.\nWith the simulation tool developed as a part of this project, charged particle\norbits are studied. Especially, the properties of the so called banana and passing\norbit topologies are studied and the observed results explained using theoretical models. We find expressions that approximately describe the width of the banana and passing orbits and the location of the banana orbit’s mirror points.\nThe orbit dependence on mass, charge and energy is investigated and an expression\nfor the particle’s deviation from a field line is derived. Also, the cause for banana orbits forming is studied and their occurrence is shown to depend on how\nthe particle’s velocity vector is directed. Finally, the two computational methods used, where either the particle or its guiding-center is followed, are compared with\nrespect to both energy conservation and computational time. The guiding-center approach is shown to greatly reduce computational cost.
Authors: M. Hoppe, Aylwin Iantchenko, Ingrid Strandberg
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2550933765