Progress of Plasma Scenario Modeling for JA DEMO

In order to proceed the integrated core plasma scenario modeling of JA DEMO, (i) core transport simulation, (ii) vertical stability and (iii) MHD stability analyses have been performed. On the 1.5-D time-dependent core transport simulation by integrated code TOPICS, the steady-state operation condition with HH98y2 = 1.41, betaN = 3.6, fBS = 0.69 is demonstrated by optimizing the heating scenario, where CDBM transport model is used. It is also demonstrated that off-axis ECCD (30MW, O-mode, 190GHz) has important roles for maintaining the internal transport barriers (ITBs) for steady-state condition and for controlling the fusion power by control of ITB location. On the vertical stability analysis, the ramp-up scenario of high elongated plasma has been developed by using the plasma equilibrium simulator MECS with 3D eddy current effects. The temporal evolutions of the poloidal beta and internal inductance are evaluated using TOPICS. The result indicates that plasma elongation at 95% of poloidal flux of 1.75 is achievable in JA DEMO. Regarding the MHD stability analysis, the beta limit of JA DEMO plasma has been evaluated by using the linear ideal MHD stability code MARG2D. The beta limit without conducting wall is betaN ~ 2.6, while that with conducting wall can be improved to ~3.5 at the wall radius of rW/a = 1.35. Further improvements are observed with decreasing the wall radius, for example betaN ~ 3.9 at rW/a = 1.30.
14th International Symposium on Fusion Nuclear Technology