Description
One of the most important issues for next generation tokamaks, as ITER and DEMO, is control of impurity accumulation in the core plasma. High Z impurities as tungsten used in the divertor wall are possible to cause strong radiation losses, which can degrade plasma performance. Integrated modelling simulations are useful to investigate evolution of plasma profiles, and impurity analyses of L- and H-modes for ITER have been performed using the integrated workflow [1]. We have been developing integrated transport simulation code TASK [2], enabling to calculate profiles both of main plasma and impurity in a self-consistent manner. Here we focus on this self-consistency, and impurity transport calculations are performed using TASK by considering the energy balance of nuclear burning and external heating. The entire of impurity profiles are calculated for L- and H-modes, though only the core region except the pedestal region is calculated for the main plasma components in H-modes. Due to the temperature shielding effect, impurities do not accumulate in the central region as same as the previous study [1]. Its dependencies on electron cyclotron heating and impurity influx are evaluated. Extension of the simulation scheme is also being carried out to introduce a surrogate model of turbulent transport and a simplified core-SOL coupling model.
[1] D. Fajardo, et al., Plasma Phys. Control. Fusion 67 (2025) 015020.
[2] M. Honda, et al., Nucl. Fusion 46 (2006) 580.