Peak neoclassical toroidal viscous force in the DIII-D tokamak

摘要

Observation of a theoretically-predicted peak in the neoclassical toroidal viscosity (NTV) force as a function of toroidal plasma rotation rate Ω is reported. The NTV was generated by applying n = 3 magnetic fields from internal coils to low Ω plasmas produced with nearly balanced neutral beam injection. The peak corresponds to a toroidal rotation rate Ω_0 where the local radial electric field E_r is near zero as determined by radial ion force balance.