ION TEMPERATURE PROFILE SIMULATION OF JT-60 AND TFTR PLASMAS WITH IONTEMPERATURE-GRADIENT MODE TRANSPORT MODELS

Ion temperature profiles of neutral beam heated plasmas in JT-60 and T FTR have been simulated using models of ion thermal diffusivity, chi(i ), based on ion temperature gradient mode (eta(i) mode) turbulence and drift wave turbulence (trapped electron mode and circulating electron mode). The ion temperature profiles measured by charge exchange recom bination spectroscopy are compared to predicted T(i) profiles calculat ed from three theoretical models for ion heat transport by Dominguez a nd Waltz, Lee and Diamond, and Romanelli. All three chi(i) models can reproduce the measured T(i) profile over a wide range of parameters in JT-60 L mode plasmas, except for two 1 MA limiter cases. With the use of transport models, which were adjusted to fit JT-60 plasmas, it was found that the Dominguez and Waltz and Romanelli models agree with me asured T(i) profiles in TFTR L mode discharges in the region a/4 < r < a/2. The observed central peaking of T(i) near the magnetic axis of T FTR L mode plasmas cannot be reproduced. It was found that the Lee and Diamond model does not fit the data as well. The chi(i) models studie d cannot consistently reproduce the measured T(i) in the peripheral re gion of either JT-60 or TFTR plasmas. In the high ion temperature (hig h T(i)) plasmas of JT-60 and supershot plasmas of TFTR, the predicted T(i) profiles are much broader than the measured profile. In supershot plasmas, the measured central ion temperature greatly exceeds the pre dicted temperature, although there is reasonable agreement near the ed ge.