1. Transport Model with Global Flow M. Yagi, M. Azumi 1, S.-I. Itoh, K. Itoh 2 and A. Fukuyama 3 Research Institute for Applied Mechanics, Kyushu University 1 Japan Atomic Energy Research Institute 2 National Institute for Fusion Science 3 Kyoto University Acknowledgement: C. Z. Cheng and T. S. Hahm (PPPL) A. Smolyakov and A. Hirose (U. Saskatchewan) P. Diamond(UCSD) Y. Kishimoto (JAERI)

2. Background co-existence Scale Length Empirically, Macroscopic dynamics ~a Microscopic dynamics ~  i, ~  e, ~  e “Bohm” “Gyro-Bohm” “k~a -1 ”,”transient”,”non-local”,”non-diffusive” “k~  i -1 ”,”transport”,”local”,”diffusive” Symmetry 1D: electric field bifurcation, interface dynamics, etc. 3D: island (Nature of transport in high temperature plasmas) Statistics Deterministic Probabilistic (chaos, intermittency) Approaches: DNS(Direct Numerical Simulation), LES(Large Eddy Simulation) 2D: covective cell(zonal flow, streamer)

3. Categorization of Phenomena in Tokamak Plasmas Based on Scale Length (Wave Number) lower hierarchy

4. Why Transport-MHD Model ?

5. Transport-MHD Model BohmGyro Bohm

6. Analysis of Heat Pulse Propagation Based on RMHD Step (1): calculate saturation state energy from initial profile based on reduced MHD model Step(2): heating source is applied in the central region at saturation stage and analyze propagation of heat pulse

7. Time Evolution of Fluctuation Energy

10. Time Evolution of Pressure(Radial Profile)

11. Heat Pulse Propagation Diffusive Non Diffusive

12. Ballistic Heat Pulse Propagation Heat flux is not described by a simple form. Heat pinch appears as non-local nature. heat pinchnormal diffusion

13. Summary Transient transport is investigated based on Transport-MHD model Heat pulse propagates ballistically ( t > 350) ExB nonlinearity plays an important role for pulse propagation The results show that Diffusion approximation sometimes fails. More quantitative analysis based on the realistic model is under construction.

14. transport flow turbulence Hierarchical transport model with flow Interaction with turbulence gives

15. Transport Model (1) (2) (3) (4)

17. Parallel momentum balance and heat flow equation Ohm’s law(4) and parallel ion flows are generally described by Reduced model: eq.(4) and Ion flow does not appear in transport model in explicit form.

18. Application of Transport-MHD model Sawtooth triggered transition between ignited state to L-mode in ITER(interaction between thermal instability and MHD) The transport simulation with sawtooth model shows the thermal quench triggered by sawtooth. Transport simulation of ITER-like plasma Thermal quench

19. Control of NTM The linear stability depends on the model. 4-field RMHD model including ion neoclassical viscosity shows combined effect with ion neoclassical viscosity and both ion and electron diamagnetic effect is crucial to stabilize NTM. These effects are not fully taken into account of the conventional Rutherford model.