TITLE

Experimental demonstration of tokamak inductive flux saving by transient coaxial helicity injection on national spherical torus experiment

AUTHOR(S)
Raman, R.; Mueller, D.; Jarboe, T. R.; Nelson, B. A.; Bell, M. G.; Gerhardt, S.; LeBlanc, B.; Menard, J.; Ono, M.; Roquemore, L.; Soukhanovskii, V.
PUB. DATE
September 2011
SOURCE
Physics of Plasmas;Sep2011, Vol. 18 Issue 9, p092504
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
Discharges initiated by transient coaxial helicity injection in National Spherical Torus Experiment have attained peak toroidal plasma currents up to 300 kA. When induction from the central solenoid is then applied, these discharges develop up to 300 kA additional current compared to discharges initiated by induction only. CHI initiated discharges in NSTX have achieved 1 MA of plasma current using only 258 mWb of solenoid flux whereas standard induction-only discharges require about 50% more solenoid flux to reach 1 MA. In addition, the CHI-initiated discharge has lower plasma density and a low normalized internal plasma inductance of 0.35, as needed for achieving advanced scenarios in NSTX.
ACCESSION #
66184773

 

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