By conducting power scan experiments using perpendicular neutral beams (NBs) after the injection of tangential NBs in directions co-, balanced and counter to the plasma current, the unified effect of counter-toroidal rotation and heating power on type-I edge-localized modes (ELMs) was investigated in a JT-60U tokamak. ELM frequency fELM increased monotonically together with the power across the separatrix Psep for all the cases of tangential NBs. However, dependence of fELM on Psep was explicitly stronger than a simple proportionality when perpendicular NBs were injected. The toroidal rotation velocity at the H-mode pedestal shifted continuously in the counter-direction when perpendicular NBs were applied. At fixed values of , fELM increased clearly in proportion to Psep. In addition, this proportionality between fELM and Psep holds regardless of the mixture of datasets of the toroidal momentum inputs. The proportional coefficient decreased as shifted in the co-direction.
Tokamak toroidal rotation caused by AVDEs and ELMs