Inter-code comparison benchmark between DINA and TSC for ITER disruption modelling

Miyamoto, Seiji*; Isayama, Akihiko; Bandyopadhyay, I.*; Jardin, S. C.*; Khayrutdinov, R. R.*; Lukash, V.*; Kusama, Yoshinori; Sugihara, Masayoshi*

Two well-established simulation codes, DINA and TSC, are compared with each other using benchmark scenarios in order to validate the ITER 2D disruption modelling by those codes. Although the simulation models employed in those two codes ought to be equivalent in the resistive time scale, it has long been unanswered whether the one of the two codes is really able to reproduce the other result correctly, since a large number of code-wise differences render the comparison task exceedingly complicated. In this paper, it is demonstrated that after simulations are set up accounting for the model differences, in general, a good agreement is attained on a notable level, corroborating the correctness of the code results. When the halo current generation and its poloidal path in the first wall are included, however, the situation is more complicated. Because of the surface averaged treatment of the magnetic field (current density) diffusion equation, DINA can only approximately handle the poloidal electric currents in the first wall that cross field lines. Validation is carried out for DINA simulations of halo current generation by comparing with TSC simulations, where the treatment of halo current dynamics is more justifiable. The particularity of each code is depicted and the consequence in ITER disruption prediction is discussed.