NSTX-U Supported by Macroscopic Stability (MS) Research Progress and Plans Jong-Kyu Park (PPPL) J. W. Berkery (Columbia University) A. H. Boozer (Columbia University) and the NSTX Research Team Coll of Wm & Mary Columbia U CompX General Atomics FIU INL Johns Hopkins U LANL LLNL Lodestar MIT Lehigh U Nova Photonics ORNL PPPL Princeton U Purdue U SNL Think Tank, Inc. UC Davis UC Irvine UCLA UCSD U Colorado U Illinois U Maryland U Rochester U Tennessee U Tulsa U Washington U Wisconsin X Science LLC Culham Sci Ctr York U Chubu U Fukui U Hiroshima U Hyogo U Kyoto U Kyushu U Kyushu Tokai U NIFS Niigata U U Tokyo JAEA Inst for Nucl Res, Kiev Ioffe Inst TRINITI Chonbuk Natl U NFRI KAIST POSTECH Seoul Natl U ASIPP CIEMAT FOM Inst DIFFER ENEA, Frascati CEA, Cadarache IPP, Jülich IPP, Garching ASCR, Czech Rep NSTX-U MS TSG discussion B252, PPPL July 13, 2012
Discussion for MS chapter in NSTX-U Five-year plan • First need to develop very clear thrusts • Need to reshuffle plans under each thrust, to modify and improve chapter outline • Define a draft list of lead and co-authors for each chapter for writing • Complete the draft time-line for MS chapter
Thrusts for MS research • Presently we have • Beta and profile control support, expected impact on stability • Error field identification and control • RWM – passive stability and active control • NTV: 3D field effects on equilibrium, transport, turbulence, etc • Disruption physics, detection, and mitigation • Need more definitive thrusts. Possibly, • For stability physics and control (Steve, Jack?) • For 3D field physics (JK, Boozer, Menard?) • For disruption detection and mitigation (Stefan, Roger?)
Plans related to stability and control • Year 1 • Recover and explore NSTX MS control capabilities • Assess the βN or q limit with new shaping control and off-axis NBCD • Recover and upgrade RWM Bp+Brand state space control with SPAs, including n>1 and multi-mode control • Year 2 • Validate RWM physics in reduced ν* and varied fast ion populations • Utilize off-axis NBCD to vary q-profile and applies to RWMs and tearing modes • Year 3 • Optimize rotation feedback control for improving RWM and TM stability • Assess and optimize tradeoffs between q, rotation, β to improve stability • Explore the lowest ν* regimes and optimize RWM and TM stability • Year 4 • Combine rotation and β feedback control to maximize performance • Provide FNSF/Pilot projection on RWM and TM stability and disruption • Year 5 • Integrate MS control to avoid RWM, TM, ELM instability, disruption, with disruption mitigation protection • Integrate validation of models for FSNF/Pilot
Plans related to 3D field physics • Year 1 • Recover and explore NSTX MS control capabilities • Identify n=1,2,3 error fields and optimize corrections with new SPAs • Year 2 • Explore NTV physics with new NBIs and SPAs • Begin implementation of rotation control with new NBIs and SPAs • Year 3 • Optimize rotation feedback control for improving RWM and TM stability • Assess and optimize tradeoffs between q, rotation, β to improve stability • Year 4 • Combine rotation and β feedback control to maximize performance • Year 5 • First use of NCC (if resources permitting) • Integrate MS control to avoid RWM, TM, ELM instability, disruption, with disruption mitigation protection • Integrate validation of models for FSNF/Pilot
Plans related disruption detection and mitigation • Year 1 • Revisit disruptivity and study halo current dynamics and heat loads on divertor • Apply MGI mitigation and explore dependency on injection locations • Year 2 • Identify disruption characteristics in various scenarios obtained by off-axis NBCD • Test and optimize MGI techniques by varying positions and actuators • Year 3 • Explore disruption precursors and avoidance scenarios with various MHD origins • Explore MGI triggering for real-time actuation for disruption mitigation • Year 4 • Provide FNSF/Pilot projection on RWM and TM stability and disruption • Couple MGI triggering techniques to mitigate disruptions • Year 5 • Integrate MS control to avoid RWM, TM, ELM instability, disruption, with disruption mitigation protection • Integrate validation of models for FSNF/Pilot
Theory/Simulation/Diagnostics • For theory and simulation, presently we have only • VALEN • IPEC • … • Key diagnostics, presently we have (Presented in PAC 31) • Real-Time Velocity measurement • Toroidally displaced MESXR • Core X-ray imaging spectrometer • Internal magnetic fluctuation measurement • Real-Time MSE and MPTS • Refurbishment of magnetic sensors including Bp and Br
Non-axisymmetric Control Coil (NCC) • Need to do the actual analysis on • Rotation control (NTV) • RWM active control (VALEN3D, done for NSTX) • RWM kinetic stabilization (MISK) • Error Field Correction (IPEC) • ELM control and stabilization (TRIP3D is done for NSTX) • Simultaneous control • Prediction for ITER 3D coil capabilities • Need to launch NCC coil design activities? • Set up coil geometries (for instance, 2 options from Steve) • Set up NSTX-U targets (a couple of targets from Stefan) • Analysis plans (codes, responsible persons) • IPEC (JK), NTV (Kimin), RWM dWk (Jack), TRIP3D (YS), VALEN3D (Jim), etc?
Summarized theory topics in MS
Important diagnostics for MS topics were identified and will be under proposal and/or development
