Comparison of two resistive ballooning mode models in transport simulations

Predictive transport simulations of the temperature and density profiles have been carried out for Tokamak Fusion Test Reactor (TFTR) [K. Young et al., Plasma Phys. Controlled Fusion 26, 11 (1984)] current, density, and heating power scans. Two competing resistive ballooning mode theories are considered in order to examine their intrinsic magnetic-q dependence. The theoretically derived transport model employed in this study includes drift wave contributions from the Weiland theory of trapped electron and ion temperature gradient modes, the Kwon-Biglari-Diamond neoclassical magnetohydrodynamic (MHD) theory, the Tang-Rewoldt kinetic ballooning mode theory, and either the previously used Carreras-Diamond or the recently developed Guzdar-Drake resistive ballooning mode theories. It is found that the Guzdar-Drake theory provides the correct scaling with plasma current while maintaining a scaling with density and auxiliary heating power that is consistent with experimental data from TFTR low confinement (L-mode) plasmas. A statistical analysis of the profile results for the current scan is included to give quantitative measures of how well simulations that include either the Guzdar-Drake or the Carreras-Diamond theory compare with the experimental data. (C) 1996 American Institute of Physics.