Numerical simulation of divertor’s topological effects on tokamak transport with resonant magnetic perturbation

Abstract

Effects of externally imposed stochastic magnetic field on plasma transport in tokamak with divertor geometry are investigated Resonant magnetic perturbations (RMPs) can enhance particle transport and eliminate the Edge Localized Modes (ELMs) When particles cross the separatrix particles hit the diverted plates and can be removed from the system This process does not allow the transport to be diffusive In the numerical simulation guiding center equation of motion is solved both in flux coordinates and Cartesian coordinates The flux coordinates in the closed field line region are employed because of its simplicity and correct response to the resonance at the mode rational surfaces The Cartesian coordinate system is applied to particle motions when particles cross separatrix because of the singularity at the X-point A mapping tool to transform the coordinate systems from one to the other is generated Employing the developed guiding center orbit following code the global density evolution and temperature evolution are discussed as well as energy spectrum of the particles which reach the divertor plates

Date of Award	2017 Sept 13
Original language	English
Supervisor	Yasutaro Nishimura (Supervisor)