Recent Progress in High Power Heating and Long Pulse Experiments on EAST

Full text: New capabilities including RF powers and diagnostics have been developed since last IAEA meeting. Totally about 3 MW H and CD power is injected into the EAST plasma. Behavior of basic plasma confinement/transport under the condition of dominant electron heating and low momentum input is investigated. Divertor performance has been systematically assessed for both SN and DN configurations with normal and reversed Bt directions. Intriguing findings, particularly, in asymmetries correlated with classic drift and in control by gas puffing at various divertor locations are studied and comparison with SOLPS modeling is being done. 1 MW LHW power injection has produced fully non-inductive plasma discharges. Such discharges have been readily extended well over one minute. Higher power up to 1.5 MW led over current driven. LHCD results fitted to the K-F model verifies classic collision picture of wave energy converted to poloidal magnetic energy, which is further confirmed by the simulations. Both direct electron and ion heating by ICRF has been observed in MC scenario, implying direct wave (ICW via MC) damping on ion. Effort is being dedicated to different heating scenarios of ICRH to address several key physical issues, such as transport control, flow driven, etc. Novel wall conditioning techniques using RF and HF glow discharges in the presence of toroidal magnetic fields have been successfully applied as well as real-time coating during plasma discharges to achieve a good wall condition. The effects of these techniques on the first wall and plasma performance are analyzed and assessed for ITER. Great efforts are being dedicated to integration of ICRH and LHCD scenarios, divertor configuration control coupled with optimized puffing and active pumping, under well conditioned wall to achieve improved plasma performance. Comparisons are being made with integrated modeling and data analysis based on IMFIT and PTRANSP. (author)