RE Nygren, Sandia ARIES Town Hall - 10-12dec2008 - UCSD Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company,

RE Nygren, Sandia ARIES Town Hall - 10-12dec2008 - UCSDSandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company,

for the United States Department of Energy’s National Nuclear Security Administration under contract DE-AC04-94AL85000.

General Comments on theDevelopment of Future Fusion PFCs

presented by Richard E. Nygren

Sandia National Laboratories

ARIES High Heat Flux Components WorkshopUCSD 10-12 December 2008

RE Nygren, Sandia ARIES Town Hall - 10-12dec2008 - UCSD

Alternates

Tokamak/AT Focus: 1. tokamak divertors

2. solid surface PFCs

3. present/ITER-DEMO gap

Other: 4. alternates

5. liquid surface

6. other fusion pathways

BROAD SCOPE


Alternates

Tokamak/AT ITERdivertor

TFTRTore Supra

JT-60U DIII-D

ASDEX-U

JET

TEXTOR

Non-electric or hybrid applications

Wendelstein

LHD

MAST

W7X

NSTX

BROAD SCOPE

C-MOD


Tokamak/AT ??????

Alternates

DEMO-B divertor

ITERdivertor

JT-60U DIII-D

ASDEX-U

JET

TEXTOR

DEMO-A divertor

Non-electric of hybrid applications

Wendelstein

LHD

MAST

W7X

NSTX ???

???

?? primary alternate

C-MOD

TFTRTore Supra

???/CTF

BROAD SCOPE


Tokamak/AT ??????

Alternates

DEMO-B divertor

ITERdivertor

TFTRTore Supra

JT-60U DIII-D

ASDEX-U

JET

TEXTOR

DEMO-A divertor

Non-electric of hybrid applications

Wendelstein

LHD

MAST

W7X

NSTX ???

???

?? primary alternate

?liquid surface

C-MOD

good efficiency high availability damage resistance

D/T plasma solid surface long pulse

???/CTF

BROAD SCOPE


Tokamak/AT ??????

DEMO-B divertor

ITERdivertor

TFTRTore Supra

JT-60U DIII-D

ASDEX-U

JET

TEXTORgood efficiency high availability damage resistance

D/T plasma solid surface long pulse

DEMO-A divertor

???/CTF

GAP 1GAP 2

WORKSHOP SCOPE

C-MOD

high temperature high reliability neutron damage

tritium retentionactive cooling



active cooling tritium retention

GAP 1GAP 2

WORKSHOP SCOPE


GAP XGAP Y

physics

Tech.

tokamak

Alt’s.


active cooling tritium retention

GAP 1GAP 2

OTHER SCOPE


Tokamak/AT ??????

DEMO-B divertor

ITERdivertor

TFTRTore Supra

JT-60U DIII-D

ASDEX-U

JET

TEXTOR

DEMO-A divertor

C-MOD

D Maisonnier et al., DEMO and Fusion Power Plant Conceptual Studies in Europe Nucl. Fusion 47 (2007) ISFNT7

K. Lackner SOFT2006

G Federici et al.,Key ITER plasma edge and plasma–material interaction issues, JNM 313–316 (2003) PSI

J Linke et al., High heat flux testing of plasma facing materials …, JNM 367–370 (2007)

V PhilippsPlasma–wall interaction, a key issue on the way to a steady state burning fusion device, Phys. Scr. T123 (2006)

SOURCES


Tokamak/AT ??????

DEMO-B divertor

ITERdivertor

TFTRTore Supra

JT-60U DIII-D

ASDEX-U

JET

TEXTOR

DEMO-A divertor

C-MOD

D Maisonnier et al., DEMO and Fusion Power Plant Conceptual Studies in Europe Nucl. Fusion 47 (2007) ISFNT7

K Lackner SOFT2006

G Federici et al.,Key ITER plasma edge and plasma–material interaction issues, JNM 313–316 (2003) PSI

J Linke et al., High heat flux testing of plasma facing materials …, JNM 367–370 (2007)

V PhilippsPlasma–wall interaction, a key issue on the way to a steady state burning fusion device, Phys. Scr. T123 (2006)

D Whyte The Challenges of Plasma-Surface Interactions for ITER & Beyond, to FESAC Nov 2008

“Greenwald” Panel Report Priorities, Gaps and Opportunities: Towards A Long-Range Strategic Plan For Magnetic Fusion Energy, FESAC Oct 2007

US ReNew Activity

Sources


“The themes were defined in terms of knowledge required prior to Demo. ... based on sound scientific principles and rigorously tested in the laboratory so that the step to a [DEMO] .. taken with high confidence of success.

“Greenwald” Panel Report


Theme B. Taming the Plasma Material Interface:

.. knowledge sufficient to design and build, with high confidence,

8. PWI: Understand and control of all processes that couple the plasma and nearby materials.

9. PFCs: Understand .. materials and processes that can be used to design replaceable components that can survive ..

10. .. Other .. : .. necessary understanding of plasma interactions, neutron loading and materials to allow design of .. any other diagnostic equipment that can survive ...

“The themes were defined in terms of knowledge required prior to Demo. ... based on sound scientific principles and rigorously tested in the laboratory so that the step to a [DEMO] .. taken with high confidence of success.



Theme C. Harnessing fusion power:

knowledge .. sufficient to design and build, with high confidence,

11. Fuel Cycle: .. manage the flow of tritium ...

12. Power: .. temperatures sufficiently high for efficient production of electricity or hydrogen.

13. Materials ..: Understand the basic materials science for fusion breeding blankets, structural components, plasma diagnostics and heating components .. high neutron fluence ..

14. Safety: Demonstrate .. safety …. minimize environmental burdens ..

15. RAMI [Reliability, Availability, Maintainability & Inspectability]: Demonstrate .. productive capacity …. validate economic assumptions ….



“Greenwald” Panel ReportFinding 6. Evaluation of current and planned

programs and summary of gaps….. The most significant gaps were: G1. …. G2. …G-5. Ability to predict and avoid, or detect and mitigate,

off-normal plasma events …G-9. Sufficient understanding of all plasma-wall interactions ….

The science underlying the interaction of plasma and material needs to be significantly strengthened to ..

G-10. Understanding of the use of low activation solid and liquid materials, joining technologies and cooling strategies ...

G-11. Understanding .. the complete fuel cycle, particularly ..G-12. An engineering science base .. effective removal of heat ...G-13. Understanding .. low activation materials .. G-14. .. guarantee safety over the plant life cycle - including ..G-15. .. efficient maintainability of in-vessel components ..



Recommendation 4. .... nine major initiatives.

I-1. .. predictive plasma modeling and validation ..,

I-2. Extensions to ITER AT capabilities .. burning AT regimes

I-3. Integrated advanced burning physics …facility .. dedicated

I-4. Integrated experiment for PWI/PFCs .. steady-state .. non-DT

I-5. .. disruption-free concepts .. performance extension device ..

I-6. .. advanced computer modeling and laboratory testing .. single-effects science for major fusion technology issues,

I-7. Materials qualification facility … (IFMIF).

I-8. Component development/testing program … multi-effect issues in critical technology .. breeding/blanket .. first wall

I-9. Component qualification facility.. high availability.. heat flux .. neutron fluence .. DT device .... (CTF).


D Whyte FESAC Presentation“The Challenges of PSI for ITER & Beyond” Nov 2008

Quiescent energy exhaust

Transient energy exhaust from plasma instabilities

Yearly neutron damage in plasma-facing materials

Max. gross material removal rate with 1% erosion yield

Tritium consumption

Issue/Gap tokamaks ITER CTF DEMO now

greatly increasing

parameters


D Whyte FESAC Presentation“The Challenges of PSI for ITER & Beyond” Nov 2008

Lack basic understanding and diagnosis of PSI processes in fusion devices → Uncertain extrapolation

Heat exhaust is primary design point for edge materials, since this Is directly related to fusion power density

Thermal efficiency .. high ambient T → Fundamentally different Physical Chemistry .. completely unexplored in fusion

devices Energy sustainment chasm to CTF & DEMO Rapid dissipation of plasma thermal energy poses major

challenges in any Demo consequences of large particulate removal on .. plasma .. & safety Tokamak edge plasmas feature extreme spatial gradients and

fluctuations levels, .. erosion prediction & control very difficult

It is hard to overstate the importance of ambient temperature for fuel control & T retention

30+ years of experience .. we should be worried/excited .. in particular the effects of having “hot walls”

RE Nygren, Sandia ARIES Town Hall - 10-12dec2008 - UCSDPower plant conceptual studies in Europe D. Maisonnier, D. Campbell, I. Cook, Nucl. Fusion 47 (2007) 1524–1532 [ISFNT7]





High temperature He-cooled divertor

Need for work on divertor systems


In contrast to the rest of the world, a typical preference of US technology people has been

one step to high tech DEMO (reactor prototype)

parallel R&D for materials and blankets (CTF)

Whose DEMO?


In contrast to the rest of the world, a typical preference of US technology people has been

one step to high tech DEMO (reactor prototype)

parallel R&D for materials and blankets (CTF)

Whose DEMO?

We have a great challenge to develop the needed

technology!

ITER activity is a revealing as we observe

the need for definition and integration in the design

along with the need to move forward in building the

machine!

RE Nygren, Sandia ARIES Town Hall - 10-12dec2008 - UCSD J. Linke et al., JNM 367–370 (2007) 1422–1431

We develop PFCs using single effects tests


We are good at developing issuesWe tend to

be optimistic (we are in fusion after all)

enjoy identifying issues and pondering problems

look toward R&D programs

Hey – nice

issu

e

Congratulations on your new issue.

You rAPER Raised some important issues I

We love issues


GAP 3: Technology Culture

testsMaterial B

Material Aproperties 2

joining

properties

mockups prototypestests tests

prototypes

rad effects testing

PFC tests

PWI tests

Material A tokamak couponslab tests lab tests

test PFC

design validation

manufacturingdevelopment

QA development

scale upVendor qual.

manufacturingacceptance

components

PWI & PFC tests component dev./qual

M a t ’l s d e v el o p m e n tWe develop

one-of-a kind units with anecdotal mockup tests.


A realistic “fully funded” technology

program, will involve a strong winnowing

of choices

for PFC materials and divertor technology

simply because of the time to develop and

prove

specific robust components for a DEMO.

GAP 3: Technology Culture

Configuration d e v e l o p m e n t

PWI & PFC tests component dev./qual

M a t ’l s d e v e l o p m e n t

STs, others Ergodic div.Super-X div. Liquid PFCs


PROGRAM & DESIGN INTEGRATIONknowledge .. sufficient to design and build, with high confidence,

Recall some excerpts from the “Greenwald” panel report:

9. PFCs: Understand .. materials and processes … design replaceable components that can survive ..

I-3. Integrated advanced burning physics …facility .. dedicated

I-4. Integrated experiment for PWI/PFCs .. steady-state .. non-DT

I-8. Component development/testing program … multi-effect issues in critical technology .. breeding/blanket .. first wall


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Documents

RE Nygren, Sandia ARIES Town Hall - 10-12dec2008 - UCSD Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company,