# MODELING OF STOCHASTIC MAGNETIC FLUX LOSS FROM THE EDGE OF A POOIDALLY DIVERTED TOKAMAK

## Abstract

OAK A271 MODELING OF STOCHASTIC MAGNETIC FLUX LOSS FROM THE EDGE OF A POOIDALLY DIVERTED TOKAMAK. A field line integration code is used to study the loss of edge poloidal magnetic flux due to stochastic magnetic fields produced by an error field correction coil (C-coil) in DIII-D for various plasma shapes, coil currents and edge magnetic shear profiles. The authors find that the boundary of a diverted tokamak is more sensitive to stochastic flux loss than a nondiverted tokamak. The C-coil has been used to produce a stochastic layer in an ohmic diverted discharge with characteristics similar to those seen in stochastic boundary experiments in circular limiter ohmic plasmas, including: (1) an overall increase in recycling, (2) a broadening of the recycling profile at the divertor, and (3) a flattening of the boundary profiles over the extent of the stochastic layer predicted by the field line integration code. Profile flattening consistent with field line integration results is also seen in some high performance discharges with edge transport barriers. The prediction of a significant edge stochastic layer even in discharges with high performance and edge radial transport barriers indicates that either the self-consistent plasma response heals the stochastic layer or thatmore »

- Authors:

- Publication Date:

- Research Org.:
- GENERAL ATOMICS (US)

- Sponsoring Org.:
- (US)

- OSTI Identifier:
- 813644

- DOE Contract Number:
- AC03-99ER54463

- Resource Type:
- Conference

- Resource Relation:
- Conference: Conference title not supplied, Conference location not supplied, Conference dates not supplied; Other Information: THIS IS A PREPRINT OF A PAPER TO BE SUBMITTED FOR PUBLICATION IN PHYSICS OF PLASMAS.; PBD: 1 Jun 2002

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; DOUBLET-3 DEVICE; FORECASTING; MAGNETIC FIELDS; MAGNETIC FLUX; PERFORMANCE; PLASMA; RECYCLING; SHEAR; SIMULATION; TRANSPORT

### Citation Formats

```
EVANS, TE,, MOYER, RA, and MONAT, P.
```*MODELING OF STOCHASTIC MAGNETIC FLUX LOSS FROM THE EDGE OF A POOIDALLY DIVERTED TOKAMAK*. United States: N. p., 2002.
Web.

```
EVANS, TE,, MOYER, RA, & MONAT, P.
```*MODELING OF STOCHASTIC MAGNETIC FLUX LOSS FROM THE EDGE OF A POOIDALLY DIVERTED TOKAMAK*. United States.

```
EVANS, TE,, MOYER, RA, and MONAT, P. Sat .
"MODELING OF STOCHASTIC MAGNETIC FLUX LOSS FROM THE EDGE OF A POOIDALLY DIVERTED TOKAMAK". United States. https://www.osti.gov/servlets/purl/813644.
```

```
@article{osti_813644,
```

title = {MODELING OF STOCHASTIC MAGNETIC FLUX LOSS FROM THE EDGE OF A POOIDALLY DIVERTED TOKAMAK},

author = {EVANS, TE, and MOYER, RA and MONAT, P},

abstractNote = {OAK A271 MODELING OF STOCHASTIC MAGNETIC FLUX LOSS FROM THE EDGE OF A POOIDALLY DIVERTED TOKAMAK. A field line integration code is used to study the loss of edge poloidal magnetic flux due to stochastic magnetic fields produced by an error field correction coil (C-coil) in DIII-D for various plasma shapes, coil currents and edge magnetic shear profiles. The authors find that the boundary of a diverted tokamak is more sensitive to stochastic flux loss than a nondiverted tokamak. The C-coil has been used to produce a stochastic layer in an ohmic diverted discharge with characteristics similar to those seen in stochastic boundary experiments in circular limiter ohmic plasmas, including: (1) an overall increase in recycling, (2) a broadening of the recycling profile at the divertor, and (3) a flattening of the boundary profiles over the extent of the stochastic layer predicted by the field line integration code. Profile flattening consistent with field line integration results is also seen in some high performance discharges with edge transport barriers. The prediction of a significant edge stochastic layer even in discharges with high performance and edge radial transport barriers indicates that either the self-consistent plasma response heals the stochastic layer or that edge stochastic layers are compatible with edge radial transport barriers.},

doi = {},

journal = {},

number = ,

volume = ,

place = {United States},

year = {2002},

month = {6}

}