Predictive simulation of tokamak transport is one of the key issues in burning plasma operation. Various transport models have been proposed and examined, but the formation of internal transport barrier has not been understood well. We consider a ballooning type transport model in which the transport coefficient is reduced as s-α decreases, where s is the magnetic shear and α is the pressure gradient associated with the Shafranov shift. Typical examples of this model are the current diffusive ballooning mode (CDBM) [1] and the drift Alfvén ballooning mode (DABM) [2]. We include these models in the one-dimensional transport code TASK/TR [3] and combine it with the two-dimensional equilibrium code TASK/EQ. The transport code calculates the time evaluation of the density, toroidal rotation velocity and temperature profiles of charged particles, neutral density and the poloidal magnetic field. The equilibrium code gives the change of the poloidal plasma shape and the shift of the magnetic axis associated with the toroidal rotation. This simulation allows us to reproduce the formation of the internal transport barrier in the high β_p plasma with a weakly positive magnetic shear, the current ramp-up plasma with negative magnetic shear, and the plasma with a current hole. The change of the toroidal rotation velocity and its effects on the transport are examined. We also make a comparison between the simulation results and the experimental observations in JT-60U and the ITPA databases.

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