Center for Promotion of Computational Science and Engineering, Japan Atomic Energy Research Institute Naka Fusion Research Establishment, Japan Atomic Energy Research Institute
Yasuaki KISHIMOTO
Naka Fusion Research Establishment, Japan Atomic Energy Research Institute
The dynamics of spheromak plasmas in coaxial helicity injection (CHI) systems has been investigated using three-dimensional magnetohydrodynamic (MHD) numerical simulations. It was found that toroidal current is driven by repetitive asymmetric plasmoid injection, which is related to the n = 1 oscillations. In addition, we propose that multiple pulse operation of the helicity injection is effective for improving confinement because it reduces the n = 1 fluctuations.
