PFC / JA - 88 - 38 Effect of Local Shear on Drift Fluctuation Driven T ' ransport in Tokamaks
نویسنده
چکیده
A theory based electron thermal diffusivity has been proposed recently which is based on electron drift wave turbulence. When account is taken for the effect of local shear changes that are produced in high poloidal beta equilibrium this theory is seen to predict the observed improvement of tokamak confinement with plasma current. Confinement is seen to be good at low poloidal beta, degrade as poloidal beta increases, and then enter an improved transport region at high poloidal beta.
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