themes: fusion landscape changed with advent of iter

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THEMES:• Fusion landscape changed with advent of ITER.• US has 10% of ITER cost but stakes for domestic program much higherKey opportunities • Fusion research can be seen as a risk management program.

– Scaleup in ITER’s BP parameters is much higher than other arsea– Strong BP connections to ITER’s PFC’s material choice (must be resolved early ~ 5 year

procurement lead time– ITER-like wall on JET is key opportunity– safety issues (e.g. T retention and dust) that will become more conspicuous with site

specific safety assessment.– Tritium removal still unresolved.– Survival of ITER’s Be wall depends on correctly modeling heat and particle flux– PWI diagnostics critical

• PPPL can be a bridge helping to PFC community, edge plasma community and edge theory community all focus on understanding real plasmas. (INTEGRATION)

• Funding critical… should link ideas to ITPA wherever applicable

Boundary Physics Science Focus Group Meeting Tuesday 8th November 2005

PURPOSE OF MEETING:• Identify high priority BP science issues for 2007 FWP.• Focus on opportunities and new initiatives. • Outcome will be compressed into 7-8 slides for RC meeting 23

November.

http://nstx.pppl.gov/DragNDrop/Science_Focus_Group_Meetings/11_08_05_FWP_preparation/

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ITPA Div/SOL High Priority Research Areas • Understanding the effect of ELMS/disruptions on divertor and first wall structures,

• Tritium retention & the processes that determine it,

• Improve understanding of SOL plasma interaction with the main chamber

• Better prescription of perpendicular transport coefficients and boundary conditions for input to BPX modeling

Medium-Term • SOL transport (parallel and drift)

• High-Z materials operational experience,

• Improve our understanding of processes that determine the core impurity level,

• The impact of the simultaneous use of different materials (e.g. tritium retention)

Possible Items for Joint Work with other TGs • Disruption physics, heat load on the plate (shielding) and mitigation.

• ELMs & understanding pedestal gradient (edge-SOL profile database)

• Design divertor diagnostics (measurement and FB control) for BPX experiments

• Helium exhaust or transport in ITB plasma

• Density limits

• Fuelling techniques and performance, influence on edge plasma and wall conditions

Diagnostics - BP related High Priority Research Areas • Determination of life-time of plasma facing mirrors used in optical systsems.• Development of measurement requirements for measurements of dust, and assessment of

techniques for measurement of dust and erosion.

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NSTX Program Addresses Broad Fusion Energy Sciences Missions Through Scientific Investigations

• Determine physics principles of ST (very high T and A ~ 1.5)

• Complement lower T and A ~ 3 experiments in addressing key scientific issues of fusion plasmas

• Support preparation for burning plasma research (ITPA, ITER) and benefit from it

• Complement ITER by establishing attractive configurations for Component Test Facility (CTF) and Demo

Spherical Torus(A ~ 1.5, 0 ~ 1)

ITER(A = 3.1, R = 6.2 m)

CTF(A ~ 1.5, R ~ 1.2 m)

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5) Boundary Physics: Interface between fusion plasmas and normal temperature surroundingsCharacterize pedestal and Characterize Li pellet & SOL of low-A, H-mode, evaporator coating effectivenesshigh P/R plasmas

Exp. Run-Weeks: 12-14 12-1417

FY05 FY07FY06 FY08

What Research Milestones in the SFG Area Should NSTX Consider for FY07-08 to Address Its Missions?

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Agenda: Tues 8th 10:30 B318

• Charles: Purpose of meeting (5 mins)• Daren: New Center for Plasma Edge Simulation (5

mins)• Stewart: Opportunities in Edge Turbulence(5 mins)• Vlad: NSTX fueling plans (5 mins)• Jim /Ken: Opportunities at JET (5 mins)• Rajesh: Community input for BPO workshop (5 mins)• Raffi: DIII-D research opportunities forum (15 mins)

• Agenda: Tues 15th 10:30 B318• Dick M.. Opportunities for research on LTX• Henry K Opportunities with Li on NSTX• Rajesh Opportunities for heat and particle transport and ELM research• Vlad: Opportunities in Divertor Physics• Charles: Opportunities to study dust and deposition• Steve Scott: (to be confirmed) Opportunities at C-modOther topics...

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Center for Plasma Edge Simulation - A SciDAC Fusion Simulation Prototype Center to Develop an Integrated,

Predictive Plasma Edge/SOL Simulation Code

• Led by C. S. Chang (NYU), D.P. Stotler – PPPL Co-PI– Involving also PPPL, ORNL, Columbia, MIT, U. Colo., CalTech,

UC Irvine, Lehigh, GA, UT-K, LBL, Rutgers.– Competitively reviewed & funded by DoE at $2M / year (~$250K

to PPPL).– Effectively increases funding base by leveraging off of existing

projects & grants: 4 SciDACs, 4 ISICs, + others.• Specific physics objectives:

– Pedestal build-up,– L-H transition & power threshold,– ELM stability & cycle.

• Directly corresponds to FESAC Priorities Panel activities:– Develop testable pedestal simulation code relevant to ITER,– Develop integrated computational model including pedestal &

SOL.

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CPES – A Synergistic, Collaborative Project Involving Theory, Simulation, Computer Science, Applied Math, & Experiment

• Core component: Chang’s existing XGC edge NC kinetic code,– Guiding center particle Hamiltonian dynamics with Monte Carlo atoms,– Simulates pedestal buildup due to neutral ionization, including self-

consistent radial potential well (Chang, IAEA, 2004),• Predicted scaling for density pedestal width similar to regression analysis of

DIII-D data.• Primary extensions:

– Import gyrokinetic & solver routines from turbulence codes GTC & GEM XGC-ET (Lee, Wang),

– Extend M3D two fluid code to edge & use to determine ELM onset & simulate ELM crash,

– Combine XGC-ET & M3D in integrated code package (Samtaney),– Replace XGC’s 2-D, single species neutral model with comprehensive

module based on DEGAS 2 (Stotler),• Add time-dependence to DEGAS 2’s main tracking routine,• Update atomic physics and plasma-material interaction data (with ORNL).

– Develop & implement gyrokinetic equations for steep gradient plasmas (Hahm).

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CPES is a Prototype FSP - Computer Science / Applied Math Tools Scalable to a Full FSP

• Data management: adaptive, automated workflow system,– Code integration & coupling (Samtaney),– Runtime monitoring; interactive & autonomic control

(Feibush),– Transparent & ubiquitous data access,– Data analysis & visualization.

• Code optimization,– Use of MPP resources (Ethier),– Development of advanced solvers to improve speed,

robustness, and accuracy.

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Opportunities in Edge Turbulence

S.J. Zweben, R.J. Maqueda, J.L. Terry, T. Munsat, J.R. Myra, T. Stoltzfus-Dueck, D.P Stotler, C.E. Bush, D. D’Ippolito, O. Grulke, J.A. Krommes, B. LeBlanc,

R. Maingi, D.A. Russell, S.A. Sabbagh, A.E. White, K.M. Williams et al

PPPL 11/7/05

• NSTX probably has the ‘best’ data on edge turbulence of any tokamak or ST (2-D vs. time, 100’s of shots)

Opportunites:• collaborate with other labs (C-Mod, TJ-II, JET, RFX ?) • continue detailed analysis (velocity fields, blob tracks)• collaborate with theorists (PPPL, Lodestar, LLNL)• improve GPI diagnostic (Nova camera, APD array ?)• make time available for dedicated XP’s next year

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Cause and origin of edge turbulence blobs

R. Maqueda 11/7/05

How, why, when do turbulence perturbations in the GPI main emission layer convert into detached, radially moving blobs?

• A variety of H-mode behavior is observed with GPI: from quiescent H-modes (no blob activity) to “continuous blobbing” activity.

• Nevertheless, blobs in H-modes (between ELMs) are isolated (much less frequent) than during L-modes.

• Blobs are also not observed soon after the L-H transition, starting only after some time.

With a systematic study of the above observations one may study the cause and origin of the turbulence blobs.

• Is there a change in confinement parameters (diffusivity) between “non-blobbing” and “blobbing” H-mode phases?

• To what extent H-mode blobs mimic the characteristics of ELMs ...are blobs “-ELMs”?• Can blobs be used to “diffuse” (some of) the H-mode particle/energy exhaust into the large,

outboard PFCs and away from the small divertor region? ...or expand the footprint at the divertor?

Are blobs “good” or “bad”?

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Serves two goals - enabling technology and physics studies

Need for particle control in NSTX plasmas

Enabling technology: develop fueling, pumping, wall conditioning techniques (SGI, CT, pellet injector, divertor cryo-pumps, staged lithium plan, hot and cold boronization, plasma boronization, improved He GDC)

Physics studies: • understand recycling sources in all-carbon machine - molecular processes, MARFE (FY05, FY06)• New promising fueling techniques (SGI, CTI)

NSTX fueling plan is part of Particle Control section of NSTX 5-year Research Plan

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Serves two goals - enabling technology and physics studies

Need for particle control in NSTX plasmas

Enabling technology: develop fueling, pumping, wall conditioning techniques (SGI, CT, pellet injector, divertor cryo-pumps, staged lithium plan, hot and cold boronization, plasma boronization, improved He GDC)

Physics studies: • understand recycling sources in all-carbon machine - molecular processes, MARFE (FY05, FY06)• New promising fueling techniques (SGI, CT)

NSTX fueling plan is part of Particle Control section of NSTX 5-year

Research Plan

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Serves two goals - enabling technology and physics studies

Need for particle control in NSTX plasmas

Enabling technology: develop fueling, pumping, wall conditioning techniques (SGI, CT, pellet injector, divertor cryo-pumps, staged lithium plan, hot and cold boronization, plasma boronization, improved He GDC)

Physics studies: • understand recycling sources in all-carbon machine - molecular processes, MARFE (FY05, FY06)• New promising fueling techniques (SGI, CTI)

NSTX fueling plan is part of Particle Control section of NSTX 5-year

Research Plan

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• Implemented in FY04, ran XP in FY05

• NSTX results to date - compatible with H-mode, fueling efficiency 0.1 - 0.3 (to be presented at FY05 Results Review)

• Experiments to continue in FY06 with improved SGI (to be presented at FY06 Research Forum)

• Expected to be an important tool in lithium experiments

• Unique contribution of NSTX to novel fueling system development. Viewed as supplemental approach for ITER

• Physics of high pressure gas jet penetration through SOL

Supersonic gas jet fueling is a unique technique studied on NSTX

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I Concept Participants

Scope

US JET

1* Ion bombardment of baffles N.Sauthoff designee N. Lam P.Coad’s work on erosion and C deposition on JET baffles should be used to motivate studies on

JET ITER Wall experiment in region of ITER Tile 18

2* Gas puff Imaging S. Zweben B. Gonsalves, C. Hidalgo

Dec visit by SZ will establish possibilities

3 LH Start with S. Bernabei J. Mailloux1.interested in sharing experience on coupling2.combined edge and LH modelling3.JET finds interaction between LH and ICRF (nearby antenna) indicating an opportunity to study waves in SOL

4* W spectroscopy K Hill, R Bell KD Zastrow VUV spectroscopy upgrade needed for ITER wall experiment but presently not funded in JET

5* PTRANSP Modelling D. McCune T. Hender Consider possibly sending a JET person to work at PPPL for a while and to help.

6* Species Mix from NPA S. Medley A. Murari JET is interested in US modelling and data analysis help

7 ICE E Fredrickson M Laxeback Question the interest level of Erik

8* NTM D Gates R Buttery Apply Rosenberg code to JET Data

9 Sawtooth MHD E Fredrickson, N Gorelenkov

Porcelli Use NIMROD, M3D to study JET NTM triggering

10 MSE upgrade B Stratton N Hawkes More data acquisition

11* ECE interpretation G Taylor E de la Luna Understand the temperature discrepancy with Thomson Scattering

12 Beta limits E Fredrickson H Wilson (York), V Riccardo, P Andrews

Do we have models of probable causes of disruptions? JET seems most interested in

understanding disruptions

13* Type V ELMs R Maingi Saarelina JET probably does not have the triangularity for type V ELMs, but needs a technical evaluation

New Ideas, seemingly highly regarded at JET

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II Concept Participants Scope

US JET

1 Tritium monitoring

C. Gentile D. Brennan Real time monitoring of tritium effluence

2 BICS technique

C. Gentile P.Coad Evaluate and relate to the work of Bernice Mills (10 yrs

ago)

3 Hydrogen Sensor

C. Skinner M. Rubel Doubtful that it would answer useful questions, but an evaluation by Charles

might change minds

4 Mixed Materials

C. Skinner F. le Guern, V. Philipps

A major project requiring US to fund the engineering and installation

5 Dust –various C. Skinner A. Loarte Not too much interest at JET, possibly better to connect to AUG studies, at any rate Alberto is the big proponent of such

studies. Possibly consider a detector below the louvers.

6 MHD stability of AT

J Menard S Pinches Can Jon do more modelling beyond the Luce collaboration?

7 Equilibrium reconstruction

L Zakarov S Garasimov How does this fit in with JET’s plans for real time plasma control?

8 US JET SL JDS P Lomas JET would welcome US SL’s

New Aspects, deserving of technical evaluation

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III Concept Participants Scope

US JET

1 RWM and AT S Sabbaugh T Luce Should Steve join the Luce collaboration?

2 TRANSP D. McCune T. Johnson JET involvement with NTCC modules

3 TRANSP D. McCune J. Ongena Extend the fusion product model with possibly a JET post-Doc or grad student

4 Turbulence Theory

T.S. Hahm X. Garbet, V. Naulin

Possibly Ernesto’s efforts can act to crystallize such theoretical efforts

5 Turbulence E. Mazzucato S. Hacquin Ongoing collaboration on X-mode reflectometry. JET is interested in US modelling and data interpretation help.

6 Alpha channelling N. Fisch D. Moreau Need to understand actual applications to JET experiments, possibly by

interacting with Lost Alpha measurements – ask D. Darrow

7 Lost Alpha Detectors

D Darrow, K. Hill V. Kiptily, A. Murari

Coming on line soon, JET worried about data analysis

8 ICRF B. LeBlanc M. NightingaleM-L Mayoral

Really need to find someone from PPPL to participate in JET ICRF experiments

9 EDGE2D modelling

J. Strachan G. Corrigan Ongoing work, but need to get W working in preparation for the ITER

wall experiment

Ongoing Collaborations, possibly some new aspects

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Spectroscopy upgrade for the beryllium wall and tungsten

divertor (project under discussion)

• Visible • UV • VUV/XUV • X-ray

Several spectroscopy systems to be modified, upgraded or reinstated :

Capability to monitor ‘standard’ impurities will be retained in all cases

Visible/UV spectroscopy

•Outer divertor line of sight

•monitoring W in divertor

Visible spectroscopy

•Two divertor viewing periscopes

• Two spectrometers for C/Be sources

Requirement to cover routinely from Z=2 (He) and Z=4 (Be) to Z=74 (W)

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VUV/XUV spectroscopy

•Install new scanning system•Upgrade or replace spectrometers to cover entire wavelength range

•New CCD detectors•Reinstate visible channels to allow W/Be source measurements

Several modifications under consideration:

•Two spectrometers with scanning mirror system

•Upper inner wall/ vertical target plate & lower inner wall/divertor

•Diagnoses Be/W/C etc.

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2005 DIII-D Research Forum• Task Force Structure

– ITER foci– ITPA activities

• Opportunities for NSTX program– ITER design decisions imminent

• 2005 ROF process– Submissions– Participation– Selection

• Recent Highlights and new opportunities

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DIII-D Research Structure

http://fusion.gat.com/exp/2005/forum.html

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Recent Highlights

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Divertor Detachment with Ar in Hybrid Regime

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ELMs in the SOL and Boundary

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Impurity Sources and Transport

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DiMES

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New Capabilities

• Double Null Pumped Divertor

• FW system– FMIT @ 60 MHz, ABB @ 100 MHz: < 3MW available

• EC system– 6 CPI gyrotrons

• Beam box rotation for counter injection

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2005 ROF Process

• Solicitation of proposals: submit via WEB by Nov. 14– Sooner the better for getting on the agenda

• Get your proposals in even if you are not going to attend

• Forum Nov. 15-17– Plenary morning session: NSTX contributions overview– Parallel sessions, multiple meeting rooms for remote participation