DIII-D RESEARCH OPPORTUNITIES FORUM FOR THE 2013 EXPERIMENTAL CAMPAIGN Review | Direct submission with log-in | Request submission without log-in
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Title	332: Demonstration of noninductive Q=5 scenario in ITER shape using off-axis NBI
Name:	Jin Myung Park parkjm@fusion.gat.com	Affiliation:	Oak Ridge National Lab
Research Area:	Steady State Heating and Current Drive	Presentation time:	Not requested
Co-Author(s):		ITPA Joint Experiment :	No
Description:	Demonstrate fully non-inductive and Q=5 condition simultaneously in ITER shape using off-axis beam and higher power ECH; This is resubmission of 2012 proposal 103.	ITER IO Urgent Research Task :	No
Experimental Approach/Plan:	Start at relatively high q95 (~6). Develop higher qmin scenario with a larger radius of qmin using off-axis beam towards simultaneously achieving the Q=5 and non-inductive goals. Focus on improving plasma confinement at ITER target of betaN~3.2 rather than trying to increase betaN. Optimize q95: move to higher (lower) q95 if fNI<1 (Q>5). Document differences between ITER SS demonstration discharges and "DIII-D standard" SS scenario in double null (DN) shape.
Background:	In 2008, fully noninductive condition was demonstrated at higher q95 but with a relatively low fusion performance (G~0.15, ITER target 0.3) [E. Doyle, NF 2010]. The discharges were not stationary and revealed significant differences from steady-state discharges in DN shape (confinement, edge pedestal, stability, fast ion confinement, ...). Experiment and modeling show a strong dependency of confinement, stability, pedestal, and noninductive fraction (fNI) on q95 [Park, IAEA2010]. Theory-based projection of such discharges to ITER shows a tradeoff between fusion performance and fNI with variation in q95, as observed in DIII-D [Murakami, IAEA2010]. This experiment aims at simultaneous achievement of the fNI=1 and Q=5 goals using off-axis beam and high power ECH. TGLF simulation suggests that a larger radius for the minimum of q helps to increase both fNI and fusion performance by maximally utilizing the benefits of low magnetic shear. As in the 2011~2012 experiments in DN shape, it is very promising to develop high qmin (~2) scenario in ITER shape using off-axis beam and high power ECH. Importantly, the power requirement for the goal is lower than the 2011 high qmin steady-state discharges in DN shape.
Resource Requirements:	All neutral beam sources with 150 beams at maximum tilt angle. All available gyrotrons
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