Comparison of ITER performance predicted by semi-empirical and theory-based transport models

Mukhovatov, V.*; Shimomura, Yasuo; Polevoi, A. R.*; Shimada, Michiya; Sugihara, Masayoshi; Bateman, G.*; Cordey, J. G.*; Kardaun, O. J. F.*; Pereverzev, G. V.*; Voitsekhovich, I.*; Weiland, J.*; Zolotukhin, O.*; Chudnovskiy, A.*; Kritz, A. H.*; Kukushkin, A.*; Onjun, T.*; Pankin, A.*; Perkins, F. W.*

The values of Q = (fusion power)/(auxiliary heating power) predicted for ITER by three different methods are compared. The first method utilises an empirical confinement time scaling and prescribed radial profiles of transport coefficients, the second approach extrapolates from especially designed ITER similarity experiments, and the third approach is based on partly theory-based transport models. The energy confinement time given by the ITERH-98(y,2) scaling for an inductive scenario with plasma current of 15 MA and plasma density 15% below the Greenwald density is 3.7 s with one estimated technical standard deviation of 14%. This translates in the first approach into an interval for Q of [6-15] at the auxiliary heating power Paux = 40 MW and [6-30] at the minimum heating power satisfying a good confinement ELMy H-mode. Predictions of similarity experiments from JET and of theory-based transport models overlap with the prediction using the empirical confinement-time scaling within its estimated margin of uncertainty.