Analysis of the KSTAR Central Solenoid Model Coil Experiment

The Korea Superconducting Tokamak Advanced Research (KSTAR) Central Solenoid Model Coil (CSMC) was tested at the National Fusion Research Center (NFRC) to verify the design and manufacturing engineering and to ensure reliable operation. The CSMC reached 8.6 T at 20 kA DC operation successfully. We also assessed the AC loss of the CSMC by means of both a sinusoidal wave with a DC offset as well as a triangular pulse. We derived a friction factor correlation of CSMC at room temperature and at cryogenic temperature (4 $\sim$ 6 K). We also investigated the variation of the friction factor during current charging. The KSTAR PF coil simulation code was validated with inlet and outlet helium temperature, mass flow rate, and pressure drop from the experimental results. The operation temperature margin of the CS1 coil of KSTAR was calculated with the revised KSTAR PF coil simulation coil.