Transport simulations of Ohmic TFTR experiments with microinstability based, profile consistent models for electron and ion thermal transport

Abstract

Transport simulations of ohmically heated TFTR experiments with recently developed microinstability based, profile consistent models for the anomalous thermal diffusivities, χe and χi, give good agreement with experimental data. The steady state temperature profiles and the total energy confinement times, τE, were found to agree for each of the Ohmic TFTR experiments simulated, including three high radiation cases and two plasmas fuelled by pellet injection. Both collisional and collisionless models are tested. The trapped electron drift wave microinstability model results are consistent with the thermal confinement of large plasma Ohmic experiments on TFTR. It is also found that transport due to the profile consistent model based on toroidal ion temperature gradient (ηi) mode transport can cause saturation in τE at the highest densities comparable to that observed on TFTR and equivalent to a neoclassical anomaly factor of three. Predictions based on stabilized ηi mode driven ion transport are found to be in agreement with the enhanced global energy confinement times for pellet fuelled plasmas.