H-Mode Power Threshold Studies on MAST

Comprehensive Theoretical Study on Threshold Power of Stimulated Brillouin Scattering in Single-Mode Fibers

We have investigated and developed a theoretical approach to explore stimulated Brillouin scattering (SBS) phenomena in single mode fiber. SBS happening threshold power condition has been studied in terms of fiber parameters and input pump power. To assess threshold power precisely, the pump depletion effect and fiber loss has been included by employing 1% criterion. The threshold exponential g...

On the difference of H-mode power threshold in divertor and limiter tokamaks

The difference in the H-mode power threshold in divertor and limiter configurations is numerically investigated by analysing the effect of boundary conditions imposed on the last closed magnetic surface (LCMS) and given by prescribed density and temperature e-folding lengths, δn and δT , respectively. It is demonstrated that the variation of δn and δT significantly affects the H-mode power thre...

A semi-analytic power balance model for low (L) to high (H) mode transition power threshold

H-Mode Pedestal and Threshold Studies Over an Expanded Operating Space on Alcator C-Mod

This paper reports on studies of the edge transport barrier and transition threshold of the High Confinement (H) mode of operation on the Alcator C-Mod tokamak [I. H. Hutchinson et al, Phys. Plasmas 1, 1511 (1994)], over a wide range of toroidal field (2.6-7.86 T) and plasma current (0.4-1.7 MA). The H-mode power threshold and edge temperature at the transition increase with field. Barrier widt...

Dependence of the L- to H-mode Power Threshold on Toroidal Rotation and the Link to Edge Turbulence Dynamics

The injected power required to induce a transition from L-mode to H-mode plasmas is found to depend strongly on the injected neutral beam torque and consequent plasma toroidal rotation. Edge turbulence and flows, measured near the outboard midplane of the plasma (0.85 < r/a < 1.0) on DIII-D with the highsensitivity 2D beam emission spectroscopy (BES) system, likewise vary with rotation and sugg...