Transport barrier formation due tothe ion-temperature-gradient (ITG)-driven mode isstudied with a low-dimensional dynamical modelcomposed of 18 mode coupling equations.This is an extention of the Hu-Horton modelcomposed of 11 mode coupling equations.The 18 degrees of freedom model describesan intermittent behaviour of cross-field thermal transport,which is related to formation of sheared poloidal flowto suppress convection due to the ITG mode.Thus an edge localized mode (ELM-)-like behaviour is observedfor the Nusselt number characterizing the cross-fieldthermal transport.
Ion temperature gradient mode and H-mode confinement