Local and global bifurcations of L-mode to H-mode transition near plasma edge in Tokamak

Abstract

Abstract The mechanism of the L-mode to H-mode transition in Tokamak is an important and difficult problem in Tokamak. In this paper, the local and global bifurcations of the Ginzburg–Landau type perturbed transport equation for the L-mode to H-mode transition near the plasma edge in Tokamak are investigated by using the theory of nonlinear dynamics. A new explanation is presented for the bifurcations of the L-mode to H-mode transition near the plasma edge in Tokamak. It is found that in Tokamak there exist not only the static L-mode to H-mode transition but also the dynamic L-mode to H-mode transition. The Hopf bifurcation and limit cycle oscillations are found for the L-mode to H-mode transition near the plasma edge in Tokamak. It is illustrated that in the case of choosing suitable parameters the normalized radial electric field near the plasma edge in Tokamak is stable.