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	307: Role of turbulent-driven and Ion pressure gradient-sustained ExB flows in Triggering H-mode
Name:	George Tynan none	Affiliation:	ZZZ
Research Area:	L-H Transition	Presentation time:	Not requested
Co-Author(s):	L. Schmitz, G.R. McKee, Z. Yan, P.H. Diamond, L. Zeng, J.A. Boedo, T.L. Rhodes, E.J. Doyle, D. Eldon	ITPA Joint Experiment :	No
Description:		ITER IO Urgent Research Task :	No
Experimental Approach/Plan:	We propose to reproduce the experimental results of the Dec 2011 L-H half-day experiment (see e.g. shot 147725) but would bring to bear a full diagnostic suite of measurements (no fast profile reflectometry or burst-mode edge TS was available during that day of experiments). We would establish the target conditions with an extended LCO regime and then plunge the midplane probe with all tips operating to obtain Reynolds stress and full fluctuation field (Ne, Te, Phi, V_parallel) measurements. The probe would plunge to ~1cm inside the LCFS and capture L-mode to LCO transition, early/mid/late LCO regime, and LCO-to-Hmode transition data. Fast profile reflectometry and burst-mode edge TS would obtain high time resolution edge profile evolution data, and 2D BES imaging would be used to obtain turbulence imaging across the LCFS. If possible, some BES channels should be configured into a 1D radial chord to obtain time-space data on fluctuation amplitude evolution aross the outer ~20-30% of the minor radius during the sequence.
Background:	The results from the 2010-2011 campaigns have provided the most detailed measurements of the L-mode/LCO/H-mode transition physics, and the picture discussed above has emerged from that work. However, we do not have a complete dataset of Reynolds stress, fluctuation amplitude, and density, temperature, velocity and E field profile evolution during the transition sequence during the same discharge. This proposal would address this important missing element, and would be aimed at providing the dataset needed to clearly and convincingly demonstrate the important dual roles of the turbulent driven shear flow, the ion pressure gradient driven flow, and the onset of the edge pedestal.
Resource Requirements:	Resource Requirements:30,330,150 Beams, ECH
Diagnostic Requirements:	Midplane probe, BES large array centered on pedestal region, DBS-5,DBS-8, fast reflectometry, CER, edge TS in burst mode.
Analysis Requirements:
Other Requirements: