The effects of radially sheared poloidal rotation on neoclassical rippling modes and the structure of neoclassical resistivity gradient driven turbulence (NRGDT) are investigated in some detail. It is shown that the growth rate of rippling instabilities decreases as the rotation shear increases and the poloidal shearing flow can reduce the turbulent fluctuation levels such that turbulence suppression occurs. By solving the transport equations numerically with the ion thermal conductivity given by a model taking the effects of E × B flow into account, a current profile in the H mode case is obtained. Examination of the MHD perturbations by using a quasi-linear theory of the tearing mode indicates that the Mirnov oscillations are suppressed when the E × B flow is introduced. A model for actively suppressing tokamak edge turbulence and hence inducing an L-H transition with the lower hybrid wave (LHW) is proposed. From the model it is found that the threshold LHW power required for edge turbulence suppression is proportional to A(ω) = (ω/ω)_(LH))~2|(ω/ω_(LH))~2-1|.
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