Particle control in the DIII-D advanced divertor

Author

Schaffer, M.J. ; Lippmann, S.I. ; Mahdavi, M.A. ; Petrie, T.W. ; Stambaugh, R.D. ; Hogan, J. ; Klepper, C.C. ; Mioduszewski, P. ; Owen, L. ; Hill, D.N. ; Rensink, M. ; Buchenauer, D.

Author_Institution

General Atomics, San Diego, CA, USA

fYear

1991

fDate

30 Sep-3 Oct 1991

Firstpage

197

Abstract

A novel, electrically biasable, semiclosed divertor was installed and operated in the DIII-D lower outside divertor location. The semiclosed divertor has yielded static gas pressure buildups in the pumping plenum in excess of 10 mtorr. Electrical bias controls the distribution of particle recycle between the inner and outer divertors by E&oarr;×B&oarr; drifts. Depending on sign, bias increases or decreases the plenum gas pressure. Bias greatly reduces the sensitivity of plenum pressure to separatrix position. In particular, E&oarr;×B&oarr; drifts in the DIII-D geometry can direct plasma across a divertor target and then optimally into the pumping aperture. Bias, even without active pumping, has also demonstrated a limited control of ELMing H-mode plasma density

Keywords

Tokamak devices; fusion reactor theory and design; plasma impurities; plasma toroidal confinement; DIII-D lower outside divertor location; ELMing H-mode plasma density; particle recycle; pumping plenum; semiclosed divertor; separatrix position; static gas pressure buildups; Cryogenics; Electrodes; Geometry; Laboratories; Plasma applications; Plasma confinement; Plasma density; Plasma temperature; Plasma waves; Tokamaks;

fLanguage

English

Publisher

ieee

Conference_Titel

Fusion Engineering, 1991. Proceedings., 14th IEEE/NPSS Symposium on

Conference_Location

San Diego, CA

Print_ISBN

0-7803-0132-3

Type

conf

DOI

10.1109/FUSION.1991.218919

Filename

218919