UC San Diego

Energy from nuclear fusion of Hydrogen isotopes is a possible alternative to fossil fuels. For this to be of practical utility, confinement of Hydrogen in a plasma state for a minimum duration is necessary. Since confinement is strongly affected by radial transport processes, understanding the observed modes of radial transport in confined plasma is of vital importance for progress towards fusion energy. The present dissertation is aimed at studying radial (cross-field) transport in the tokamak edge plasma. The present thesis is divided into three parts : In the first part, we present a model of generation of intermittent convective meso-scale structures (blobs) based on the synergy of the interchange drive and nonlinear effects associated with drift-wave turbulence. In the second part, we attempt to explain the preferential propagation of blobs radially outward as a consequence of the radially decreasing density of a confined plasma. In the third part, we present a model for simulating anomalous radial transport in kinetic codes for tokamak edge plasma