Results of hydrogen pellet injection into ISX-B

Lithium Pellet Injection Experiments

A pellet enhanced performance (PEP) mode, showing significantly reduced core transport, is regularly obtained after the injection of deeply penetrating lithium pellets into Alcator C-Mod discharges. These transient modes, which typically persist about two energy confinement times, are characterized by a steep pressure gradient (4, <a/5) in the inner third of the plasma, indicating the presence ...

ECRH Results during Current Ramp-up and Post-Pellet Injection in FTU Plasma

Recent ECRH experiments in FTU have provided new results in two plasma scenarios, both characterized by the absence of the sawtooth activity and by flat or reversed q profiles. The first is the current ramp-up phase where low density plasmas have been heated up to high electron temperature. When the heating is localized on the plasma axis, the high additional power density has produced the evid...

3D adaptive mesh refinement simulations of pellet injection in tokamaks

Injecting small pellets of frozen hydrogen is a proven method of fueling tokamaks but a quantitative theory of mass redistribution during inside/outside injection is still lacking. We present results of Adaptive Mesh Refinement (AMR) simulations that quantify the MHD processes responsible for mass redistribution. AMR is essential to provide the resolution required to simulate realistic pellet s...

Effect of Transport Processes on Tokamak Refueling by Pellet Injection

The Cit Pellet Injection System: Description and Supporting

The Compact Ignition Tokamak (CIT) will use an advanced, high-velocity pellet injection system to achieve and maintain ignited plasmas. Two pellet injectors are provided: a moderate-velocity (1 to 1 S-km/s), single-stage pneumatic injector with high reliability and a high-velocity (4to 5-km/s), two-stage pellet injector that uses frozen hydrogenic pellets encased in sabots. Both pellet injector...