Energy confinement time τE and its scaling law in the NanChang Spherical Tokamak (NCST) are investigated based on experimental data from NCST campaigns, with a focus on their dependence on plasma current (IP), toroidal magnetic field (BT), and electron density (ne). Multivariate fitting results indicate that τE exhibits a weak nonlinear dependence on BT and a weaker dependence on IP, while its dependence on ne is extremely weak. Single-parameter scanning results further confirm the key dependencies on IP and BT. These findings contribute to the broader physics understanding of confinement in low-aspect-ratio tokamaks and inform the design of future spherical tokamaks such as the NCST-U.
Chen et al. (Sun,) studied this question.