Design of the KSTAR Divertor

• Published in: Fusion technology 2000-03, Vol.37 (2), p.110-123
• Main Authors: Lee, BongJu, Hill, David, Im, K. H., Sevier, L., Han, Jung-Hoon, Braams, Bastiaan J.
• Format: Article
• Language: English
• Subjects: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; Applied sciences; Carbon fibers; Composite materials; Controled nuclear fusion plants; DESIGN; DIVERTORS; Elementary particle sources; Energy; Energy. Thermal use of fuels; Exact sciences and technology; Fusion reactors; HEAT FLUX; Heat radiation; Installations for energy generation and conversion: thermal and electrical energy; Magnetic confinement and equilibrium; MATHEMATICAL MODELS; Monte Carlo methods; Physics; Physics of gases, plasmas and electric discharges; Physics of plasmas and electric discharges; PLASMA IMPURITIES; Plasmas; Pressure control; Superconducting magnets; TOKAMAK DEVICES; Tokamaks
• ISSN: 0748-1896
• DOI: 10.13182/FST00-A127

The planned Korea Superconducting Tokamak Advanced Research (KSTAR) divertor has been designed to provide reliable power handling and particle control with enough shaping flexibility to accommodate a wide range of plasma operation. The physics basis for the current configuration of the KSTAR divertor through analyses of the heat flux at the target, particle control, and plasma-facing component is reported. A simple zero-dimensional model based on the power balance assumptions and two-dimensional codes is utilized to estimate the heat flux to the divertor plate. The limit for the peak heat flux on the divertor plate, 3.5 MW/m 2 , requires advanced operating modes such as the radiative divertor and radiative mantle, which are considered to overcome the weakness of a high-recycling divertor. A simple particle balance model could estimate the pumping rate with total leakage fraction assuming particle sources. A Monte Carlo neutral transport calculation determines the dimension of a gap between the center and outer divertor targets. It also determines the number and best position of the pumps, as well as the geometry for conductance. For the initial 20-s discharges, a bolted-tile carbon-fiber-composite design is relied upon for the upper and lower divertor targets. The design of the supporting structure for the divertors will allow for future modifications to accommodate thermal steady-state 300-s operation or to optimize divertor performance based on new understanding gained during initial tokamak operation.