2016/01/01 by R.D. Smirnov, R. D. Smirnov, A.S. Kukushkin +5 · 1 citation
Engineering · Materials Science · Physics and Astronomy · #Fusion materials and technologies #Magnetic confinement fusion research #Superconducting Materials and Applications
paper · doi:10.1063/1.4939539
openalex publication_date 2016/01/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/29
Two different oscillatory plasma regimes induced by seeding the plasma with high- and low-Z impurities are found for ITER-like divertor plasmas, using computer modeling with the DUSTT/UEDGE and SOLPS4.3 plasma-impurity transport codes. The oscillations are characterized by significant variations of the impurity-radiated power and of the peak heat load on the divertor targets. Qualitative analysis of the divertor plasma oscillations reveals different mechanisms driving the oscillations in the cases of high- and low-Z impurity seeding. The oscillations caused by the high-Z impurities are excited near the X-point by an impurity-related instability of the radiation-condensation type, accompanied by parallel impurity ion transport affected by the thermal and plasma friction forces. The driving mechanism of the oscillations induced by the low-Z impurities is related to the cross-field transport of the impurity atoms, causing alteration between the high and low plasma temperature regimes in the plasma recycling region near the divertor targets. The implications of the impurity-induced plasma oscillations for divertor operation in the next generation tokamaks are also discussed.