Gyrokinetic analyses of core heat transport in JT-60U plasmas with different toroidal rotation direction
JT-60Uにおけるトロイダル回転方向の変化を伴ったコア部熱輸送のジャイロ運動論解析
成田 絵美*; 本多 充; 林 伸彦; 浦野 創; 井手 俊介; 福田 武司*
Narita, Emi*; Honda, Mitsuru; Hayashi, Nobuhiko; Urano, Hajime; Ide, Shunsuke; Fukuda, Takeshi*
The internal transport barriers (ITBs) formed in the tokamak plasmas with the weak magnetic shear and the weak radial electric field shear are often observed and the pressure gradient at the ITB is not very steep. In such plasmas the electron temperature ITB is steeper for co toroidal rotation cases than that for counter rotation cases. Clarifying the relationship between the rotation direction and heat transport in the ITB region, dominant instabilities are examined by the flux-tube gyrokinetic code GS2 to show that the linear growth rates for the co and counter rotation cases are comparable in magnitude, but the counter case shows the more trapped electron mode like frequency. The ratio of the electron heat diffusivity to the ion's is higher for the counter-rotation case. The difference in the ratio between the two cases agrees with the experiment. Investigating the flow shear effect on reveals that its effect is not so large as to change the aforementioned tendency.