Analysis of ITER operational space with as-built stiffness of central solenoid modules

The as-built stiffness in the ITER central solenoid (CS) modules (CSM1 and CSM2 are currently manufactured) determines the range of vertical compression forces that can be tolerated by the CS during ITER operation. Analysis of the ITER operational space has been performed assuming that all six CS modules have a conservative stiffness (25GPa) lower than that of CS modules manufactured (~32GPa and ~34GPa for CSM1 and CSM2, respectively). The codes CORSICA and DINA have been used to explore the plasma equilibrium operational space (the plasma internal inductance versus the poloidal magnetic flux produced by the coils) at burn in 15 MA Q = 10 DT baseline scenario. In the studies, the codes used slightly different constraints on the plasma boundary shape. The as-built stiffness of the CS modules has been also used to update scenario of plasma start-up with fully charged CS. The value of poloidal magnetic flux at initial CS magnetization in the updated plasma start-up is 116.2 Wb, slightly reduced from the previously obtained value of 117.5 Wb. 15 MA Q = 10 DT baseline scenario has been re-developed using the DINA code with the updated plasma start-up. In this scenario, the as-built stiffness of the CS modules affects only the plasma initiation. The study of 12.5 MA Q > 5 hybrid and 10 MA Q ~ 5 steady-state scenarios performed with the CORSICA code have shown that these scenarios are well within the CS force limits derived from the as-built stiffness.