Edge, Sol, and Diverter Plasma Turbulence and Macroscopic Transport

Technical Report · Mon Apr 25 04:00:00 EDT 2005

DOI:https://doi.org/10.2172/841026· OSTI ID:841026

Krasheninnikov, Sergi ^[1]

---

1. The Regents of the Univ. of CA, San Diego

In the last few years, it was clearly shown that cross-field transport in the far SOL could be significantly faster than previously thought and that this transport exhibited convective rather then diffusive features. As a result, in high density cases the plasma coming into the SOL from the core recycled at the wall of the tokamak main chamber, rather than flowing into the divertor and recycling there, as the conventional picture of edge plasma flows would suggest. It was also shown that coherent structures, often called ''blobs'', played very important roles in the particle and energy transport inside the SOL region for both L and H confinement modes. The blobs seen in the SOL are extended along the magnetic field lines and have a plasma density two to three times higher than the ambient SOL plasma density and poloidal and radial scales of about 1 cm. In experimental measurements, the blobs propagated in radial direction towards the chamber wall with a velocity {approx} 10{sup 5} cm/s, and the contribution of non-diffusive flux associated with transport of blobs to the total particle flux in the far SOL attained 70-90%. In addition, recent assessment of experimental data and theoretical models shows that plasma propagation into the SOL during ELM is somewhat similar to that of blobs.

• Research Organization: The Regents of the University of CA, San Diego
• Sponsoring Organization: USDOE
• DOE Contract Number: FG03-00ER54568
• OSTI ID: 841026
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
CONFINEMENT
DIVERTORS
MAGNETIC FIELDS
PLASMA
PLASMA DENSITY
RECYCLING
SOLS
TRANSPORT
TURBULENCE
VELOCITY
edge plasma
turbulence flows
anomalous transport
plasma-material