Full tokamak discharge simulation of ITER by combining DINA-CH and CRONOS

Abstract

A full tokamak discharge simulator has been developed by combining a freeboundary equilibrium evolution code, DINA-CH, and an advanced transport modelling code, CRONOS. The combined tokamak discharge simulator provides a full simulation of a whole tokamak discharge, including nonlinear coupling effects between the evolution of the free-boundary plasma equilibrium and transport. The free-boundary plasma equilibrium evolution is self-consistently calculated with the plasma current diffusion, in response to currents flowing in the PF coils and the surrounding conducting system. The heat and current source profiles calculated taking the free-boundary plasma equilibrium are used for the plasma transport. The constraints in operating a tokamak, such as the PF coil current and voltage limits, are taken into account. The potential of the combined tokamak discharge simulator is demonstrated by simulating whole operation phases of the inductive 15 MA ELMy H-mode ITER scenario 2. Issues related to ITER operation, such as respecting the coil current limit, vertical instability and poloidal flux consumption, are investigated. ITER hybrid mode operation is studied focusing on the capability of operating the plasma with a stationary flat safety factor profile.

Development of vector following mesh generator for analysis of two-dimensional tokamak plasma transport

“…A time-varying adaptive grid is required for multi-dimensional and time-dependent transport modeling of tokamak plasmas where the plasma equilibrium evolves in time in response to plasma transport [1] and also to currents flowing in the surrounding conducting structures [2]. In addition, a spatially inhomogeneous adaptive grid is needed for integrated transport modeling dealing with different spatial scales.…”

Robust control of the safety factor profile and stored energy evolutions in high performance burning plasma scenarios in the ITER tokamak

“…Our future work includes (i) testing the controller in the DINA-CH&CRONOS free-boundary tokamak simulation code [19] and (ii) tailoring the q-profile controller to the DIII-D tokamak geometry and experimentally testing the algorithm in DIII-D.…”

Edge equilibrium code for tokamaks

“…Its shape is determined by matching the core and the boundary layer solutions. Because of this, the boundary condition at the virtual boundary is of the Neumann type (10). It is automatically included into the matrix equations (31) after minimization of the quadratic form W (29).…”

“…In addition to the well established use of equilibrium codes 1,2 for controlling the shape of tokamak plasmas and for magneto-hydrodynamic (MHD) stability studies, new applications include the sophisticated control of vertical stability with realistic models for plasma external structures, 3,4 the analysis of variances in equilibrium reconstruction, [5][6][7] special equilibrium solvers in transport simulations (e.g., Refs. [8][9][10], and refined calculations of the plasma core and of the plasma edge. The literature on equilibrium calculations is extensive.…”