# Presentation: 485971

## Next Step Option (NSO) 

**Next Step Option (NSO)**** **

**Dale Meade**
**US ITER Project/VLT Meeting**
**Princeton, NJ**
**October 21, 2004**

## The Next Step Option (NSO) Activity

- •  NSO-PAC: 15 members, Chaired by Tony Taylor, 5 meetings, all reports are on the web ***at http://fire.pppl.gov/nso_pac5.html***
- •  FIRE effort evolved form the US ITER Design Home Team,and involved  >15 institutions and >50 individuals.
- •  FIRE has been engaged in a PreConceptual design activity at a budget of ≈ $2M/year with FY04 =FY05 = $0.6 M. The FIRE PreConceptual design was completed in FY04.

**The Next Step Option (NSO) Activity**

## NSO/FIRE Status

- Developed “Steady-state” High- AT Mode for FIRE
- Expanded Operating Range for H-Mode and AT, longer pulse, faster rep rate
- AT duration limited by first wall more than TF in present design
**PVR March 29-30, 2004**
- 		Strong positive recommendations from the PVR Committee
- 		Technically Ready to begin Conceptual Design
- Identified areas for more R&D – (most in common with ITER)
**Pre-Conceptual Design Completed - September 30, 2004**
- 		Original Goals Exceeded
- 		Excellent Technology support from VLT Team
- 		Strong Support from the Base Program (both Technology and Physics)
**Documentation is on web (needs to organized/indexed)**

**NSO/FIRE Status**

## time,(current redistributions) 

**“****Steady-State” High-******** Advanced Tokamak Discharge on FIRE**

- 0               1                 2                 3                4

- time,(current redistributions)

## ARIES-like AT Mode Operating Range Greatly Expanded

- Nominal operating point
- 	• Q = 5
- 	• Pf = 150 MW,
- 	• Pf/Vp = 5.5 MWm-3 (ARIES)
- 	• ≈ steady-state 4 to 5 CR
- Physics basis improving (ITPA)
- 	• required confinement H factor
-         and N attained transiently
- 	• C-Mod LHCD experiments
- 	  will be very important
- First Wall is the main limit
- 	• Improve cooling
- 	• revisit FW design

- Opportunity for additional improvement.

## NSO/FIRE Status

- Developed “Steady-state” High- AT Mode for FIRE
- Expanded Operating Range for H-Mode and AT, longer pulse, faster rep rate
- AT duration limited by first wall more than TF in present design
**PVR March 29-30, 2004**
- 		Strong positive recommendations from the PVR Committee
- 		Technically Ready to begin Conceptual Design
- Identified areas for more R&D – (most in common with ITER)
**Pre-Conceptual Design Completed - September 30, 2004**
- 		Original Goals Exceeded
- 		Excellent Technology support from VLT Team
- 		Strong Support from the Base Program (both Technology and Physics)
**Documentation is on web (needs to organized/indexed)**

**NSO/FIRE Status**

## FIRE PVR 

- FIRE Physics Validation Review (PVR) was held March 30-31 in Germantown.
-  The Committee included:  S. Prager, (Chair) Univ of Wisc, Earl Marmar,  MIT, N. Sauthoff PPPL, F. Najmabadi, UCSD, Jerry Navratil, Columbia (unable to attend), John Menard PPPL, R. Boivin GA,  P.  Mioduszewski ORNL, Michael Bell, PPPL, S. Parker Univ of Co, C. Petty GA, P. Bonoli MIT, B. Breizman Texas,
**PVR Committee Consensus Report:**
**The FIRE team is on track for completing the pre-conceptual design within FY 04. FIRE would then be ready to launch the conceptual design.  The product of the FIRE work, and their contributions to and leadership within the overall burning plasma effort, is stellar**.
- Is the proposed physical device sufficiently capable and flexible to answer the critical burning plasma science issues proposed above?
-    **The 2002 Snowmass study also provided a strong affirmative answer to this question.  Since the Snowmass meeting the evolution of the FIRE design has only strengthened ability of FIRE to contribute to burning plasma science.**

## FIRE PVR (2) 

- • The panel identified FIRE-specific areas that can benefit from further pre-conceptual design work including: alpha driven instabilities, generic port plug design, more modeling of particle exhaust, n>1 resistive wall modes and neoclassical modes.
- The panel also identified generic burning plasma areas that can benefit from further work : investigation of the suppression of neoclassical tearing modes (NTM) by RF current drive, development of modified and new diagnostics for burning plasma research, development of an integrated simulation capability applicable to burning plasmas, investigation of effects of ELMs on tungsten divertor components and systematic antenna development.   Possible elements in a US burning plasma program.
**Nearly all these items are also on the ITER task list**.

## NSO/FIRE Status

- Developed “Steady-state” High- AT Mode for FIRE
- Expanded Operating Range for H-Mode and AT, longer pulse, faster rep rate
- AT duration limited by first wall more than TF in present design
**PVR March 29-30, 2004**
- 		Strong positive recommendations from the PVR Committee
- 		Technically Ready to begin Conceptual Design
- Identified areas for more R&D – (most in common with ITER)
**Pre-Conceptual Design Completed - September 30, 2004**
- 		Original Goals Exceeded
- 		Excellent Technology support from VLT Team
- 		Strong Support from the Base Program (both Technology and Physics)
**Documentation is on web (needs to organized/indexed)**

**NSO/FIRE Status**

## Issues and Recommended Approach

**Follow FESAC recommendations**
- 		Support the ITER process, more aggressive outreach is needed		 to get greater community involvement in ITER.
- Stay on track,  and “Hold our FIRE” as per FESAC/NRC
**NSO was chartered for this situation**
- 	Proposed Option “extend performance of ITER using Advanced Tokamak operation”
- 		Fully exploit the capability of ITER (increase power to ~1GW at steady-state)
- 		Would address several physics tasks requested by IT Leader
- 		Coincident with US program emphasis on advanced physics and technology
- 		Aligns with FIRE mission if ITER does not go forward

**Issues and Recommended Approach**

## Magnets and PFCs (power and particle-handling, including tritium inventory):
How disruptions/VDEs which may affect the ITER design. 
Characterization of thermal energy load during disruption
Model development of halo current width during VDEs based on experiments
Simulations of VDEs in ITER with 3D MHD code
Disruption mitigation by noble gas injection
Oxygen baking experiment, which could be possible during spring 2005 at D III-D and is under discussion at GA, may be one of the possible tasks.
Heating and Current-drive and advanced control:
ITER Plasma Integrated Model for ITER for Control
Feasibility study of ITER SS scenarios with high confinement, NBCD, ECCD, LHCD, ICCD and fueling by pellet injection.
RF launchers
Validation of enhanced confinement models and application to ITER. 
Development of Steady State Scenarios in ITER
RWM in Steady State Scenario in ITER
Evaluation of Fast Particle Confinement of ITER
Diagnostics:
Specific diagnostic design tasks, including updating procurement packages[activities related to the diagnostics for which the US is responsible]

- How disruptions/VDEs which may affect the ITER design.
- Characterization of thermal energy load during disruption
- Model development of halo current width during VDEs based on experiments
- Simulations of VDEs in ITER with 3D MHD code
- Disruption mitigation by noble gas injection
- Oxygen baking experiment, which could be possible during spring 2005 at D III-D and is under discussion at GA, may be one of the possible tasks.
- Heating and Current-drive and advanced control:
- ITER Plasma Integrated Model for ITER for Control
- Feasibility study of ITER SS scenarios with high confinement, NBCD, ECCD, LHCD, ICCD and fueling by pellet injection.
- RF launchers
- Validation of enhanced confinement models and application to ITER.
- Development of Steady State Scenarios in ITER
- RWM in Steady State Scenario in ITER
- Evaluation of Fast Particle Confinement of ITER
- Diagnostics:
- Specific diagnostic design tasks, including updating procurement packages[activities related to the diagnostics for which the US is responsible]

**Physics Tasks Requested  by the International Team Leader****[US ITER Project Status  @  TOFE , 9/04]**

**Notes:**
Characterization of thermal energy load during disruption (GA)
Model development of halo current width during VDEs based on experiments (GA)
Simulations of VDEs in ITER with 3D MHD code (PPPL)
Disruption mitigation by noble gas injection (GA)
NTM control in Inductive and Hybrid Scenario in ITER (Y. Gribov, V. Mukhovatov)
	Code benchmarking, experimental validation of models of NTM and stabilization by ECCD and their application to ITER parameters. Development of models of the effect of sawteeth, error fields and pellet injection, their experimental validation and evaluation with ITER parameters [DIII-D team]
RWM in Steady State Scenario in ITER (Y. Gribov)
	Code benchmarking of RWM growth rate for Scenario 4 plasmas.
	Evaluation of RWM feedback control, effect of blanket modules, vacuum vessel ports, plasma rotation and error field, diagnostics for RWM control and background noise. [DIII-D team, Navratil]
VDE, Disruptions and their mitigation in ITER (M. Sugihara)
	Validation of the codes in experiments, simulation of disruptions in Scenario 2,
	effect of blanket modules, 3D halo currents, impurity generation / transport / radiation loss for the assessment of beta drop during VDEs, simulation of high-pressure noble gas jet penetration into Scenario 2 plasma, design requirements to the ITER system of disruption mitigation, evaluation of the effects of radiation produced by gas injection on the first wall and diagnostic system. [partial scope by DIII-D team, emphasizing gas injection mitigation]
 ITER Plasma Integrated Model for ITER (A. Polevoi/Y. Gribov)
	Development and benchmarking of code modules for impurity radiation and diffusion, edge pedestal, divertor/sol, pellet fueling, heating and current drive by including LH and IC for efficient and reliable integrated modeling of ITER [C. Kessel]
Development of Steady State Scenarios in ITER (A. Polevoi)
	Validation of enhanced confinement models and application to ITER. Feasibility study of ITER SS scenarios with high confinement, NBCD, ECCD, LHCD, ICCD and fueling by pellet injection. [C. Kessel]
Evaluation of Fast Particle Confinement of ITER (V. Mukhovatov)
	Evaluation of the effect of fishbone oscillations, TAE modes and toroidal ripple on the fast particle loss [Gorolenkov and White]
Specific diagnostic design tasks (refer to the attachment Attachment 1) [activities related to the diagnostics for which the US is responsible]
RF launchers [ICRH antenna studies by Bachelor and Phillips]
diagnostics [same as above]
control [similar to above on modeling]
disruptions/VDEs which may affect the ITER design. [Jardin/Wesley?]
Oxygen baking experiment, which could be possible during spring 2005 at D III-D and is under discussion at GA, may be one of the possible tasks. [DIII-D to consider]
walls, RF launchers, diagnostics, control and disruptions/VDEs which may affect the ITER design, Oxygen baking experiment (which could be possible during spring 2005 at DIII-D)

## FY05 Plans Highlighting ITER Support

- 		Initial results to be presented at IAEA and ITPA
- N ≈ 3.3, fbs ≈ 50% with 100% non-inductive drive (NINB, LHCD, bootstrap)
- 		LH for off-axis CD can put qmin at r/a ~0.8, compare with ECCD
- 		Lots of opportunity for improvement!!
- 		      Optimize NIND, ICFW, ECCD and LHCD mix and plasma startup(ITPA)
**Evaluate RWM feedback stabilization requirements and integrate with first wall**
- 		Initial results from Columbia (VALEN, DIII-D) look promising
- 		      stable up to  N = 3.7, for coils inside VV, integrated with shield modules
- 		Key issue is the technical feasibility of coils near the plasma
- 		      Interest expressed by G. Janeshitz in RWM in port plug first wall
- 		Resources for design of integrated first wall and coil are already over committed.

**FY05 Plans Highlighting ITER Support**

## First Results from ITER-AT Studies 

**First Results from ITER-AT Studies**
- Using TSC,TRANSP and NOVA-K

- Goal is Steady-State, N ≈ 3.5, fbs > 60% fbs , Q > 5 using NINB, ICFW and LHCD

- This case has N ≈ 3.3, fbs ≈ 44%, ≈ 100% non-inductive and  Q ≈ 5.

- IAEA Paper FT/P7-23

- Invited to join ITPA Integrated Modeling paper at IAEA and Nuclear Fusion.

## FY05 Plans Highlighting ITER Support

- 		Initial results to be presented at IAEA and ITPA
- N ≈ 3.3, fbs ≈ 50% with 100% non-inductive drive (NINB, LHCD, bootstrap)
- 		LH for off-axis CD can put qmin at r/a ~0.8, compare with ECCD
- 		Lots of opportunity for improvement!!
- 		      Optimize NIND, ICFW, ECCD and LHCD mix and plasma startup(ITPA)
**Evaluate RWM feedback stabilization requirements and integrate with first wall**
- 		Initial results from Columbia (VALEN, DIII-D) look promising
- 		      stable up to  N = 3.7, for coils inside VV, integrated with shield modules
- 		Key issue is the technical feasibility of coils near the plasma
- 		      Interest expressed by G. Janeshitz in RWM in port plug first wall
- 		Resources for design of integrated first wall and coil are already over committed.

**FY05 Plans Highlighting ITER Support**

##  Increases limit from N = 2.5 to 3.7 

- ITER

- RWM coils located outside TF coils

**Applying FIRE-Like RWM Coils to ITER**
** ****Increases ********limit from ********N**** = 2.5 to 3.7**

- Engineering feasibility needs to be determined
- G. Janeschitz has expressed interest in RWM coils integrated with first wall

- IAEA Paper FT/P7-23

- VALEN Analysis- Columbia

## FY05 Plans Highlighting ITER Support(2)

**	****   **if AT scenario yields extended performance  (~1,000+ MW),
- 	   ITER will need a first wall capable of higher power (~ 1MWm-2)
- 	     recovering  performance approaching the original ITER is the ultimate goal
**More Proactive Outreach for ITER and Burning Plasma Program**
- 		US ITER Project Info on web at ***http://fire.pppl.gov/iter_us_news.html***
- 		Two Symposia at AAAS Annual Meeting (Feb 2005) in Washington, DC on
- 			 Energy and Fusion (Talk on ITER-NRS)
- 		KPS-DP: Special Lecture on Burning Plasmas
**Community Workshop next Spring on Burning Plasma Activities**

**FY05 Plans Highlighting ITER Support(2)**

## Slide 17

## Concluding Remarks

**• ****Special thanks and a debt of gratitude to the VLT/FIRE team members for their “stellar” work on/under FIRE.**
**• ****Maintain FIRE at a holding position to be put forward as an attractive burning plasma experiment if the ITER negotiations remain deadlocked.**
**• ****Transition of NSO activities to supporting the “option” of extending ITER performance using AT operation has been accomplished without missing a step.  The goal is to recover most of the capability of the larger ITER. Already some progress.**
**• ****Need to stay the course with community strategy as events unfold.**
**• ****We must expand the fusion outreach activities in any eventuality.**

**Concluding Remarks**