Phase dynamics of edge transport bifurcation in plasma interchange turbulence*

The mechanism of turbulence suppression of transport bifurcation is investigated using a flux-driven nonlinear fluid model. Both spatial structures and frequency spectrums of potential during different states are shown, revealing the process of turbulence decorrelation by the mean E × B shear flow. Along with the amplitude of fluctuations, the phase angle between pressure and radial E × B velocity fluctuations is also modified dramatically by the self-generated mean E × B shear flow, which contributes to turbulence suppression as well.