Mohamed Abdou

1
Chamber Technology (CT) and Why Now?
Mohamed Abdou
Presented to VLT-PAC
General Atomics, San Diego February 25, 2003
Note specifics are for MFE Chamber. See Wayne
Meier for specifics on IFE Chamber
2
Outline

• What is Chamber Technology? and its central role
  in fusion devices, burning plasma devices, and
  fusion energy systems
• Past achievements and tremendous impact on plasma
  physics research and fusion energy development
  (prior to Restructuring)
• Recent achievements and Impact on fusion program
  (post restructuring)
• Critical Technical Issues for Chamber Technology
  and their Central Role in the Fusion Program for
  the next few years and beyond.
• Plans for immediate future FY04/05/06 and Role of
  Chamber Technology in Recent Initiatives ITER,
  Energy-Based Policy, and 35-yr Plan
• Disastrous consequences to the Fusion Program of
  close out of CT

Note Prior to the Restructuring of the Fusion
Program of 1997, Chamber Technology was divided
into several programs (Neutrons, Blanket/FW, Fuel
Cycle, etc.) After restructuring, these programs
were combined under a Chamber Technology Program.
3
Scope of Chamber Technology Research
Chamber Technology (CT) Research embodies the
scientific and engineering disciplines required
to understand, design, develop, test, build, and
operate safely and reliably the systems that
surround a burning plasma.CT includes all
components and functions from the edge of the
plasma to the magnets, including

• first wall
• blanket (breeding and non-breeding)
• conducting shells
• vacuum vessel
• radiation shielding
• nuclear part of RF antenna, etc.

• cooling systems
• electric/thermal insulators
• tritium barriers and processing
• tritium fuel cycle
• support structure remote maintenance

• CT also includes design and integration for
  Chamber Components

4

• Chamber Technology Embodies Two of the Three
  Fundamental Functions of Fusion Energy Systems

Fusion Energy Systems Fundamental Functions
1- Producing energy from the DT fusion reaction
in the plasma
2- High-temperature power extraction in a
practical, safe, and economical fusion energy
system (extracting heat in any plasma device)
3- Breeding sufficient tritium to assure that the
plasma is self-sustained and that fusion is a
renewable energy source with a closed fuel cycle

• The Chamber Technology Program includes all
  components required to achieve functions 2 and
  3
• Chamber Technology also embodies the systems that
  hold, provide the vacuum and fuel the plasma,
  which are essential to achieving function 1

5
The CT Program is responsible for advancing and
providing state-of-the-art predictive
capabilities for many technical disciplines
required for the fusion program
(to support, for example, Safety, Materials, PFC,
Advanced Design Studies, fusion devices, burning
plasma experiments, etc.)
Modeling, experiments, codes and analysis for

• neutron/photon transport
• neutron-material interactions
• heat/mass transfer
• thermofluid physics and MHD
• thermal hydraulics
• Tritium release, extraction, inventory and control

• structural mechanics
• thermomechanics
• chemistry
• radioactivity and decay heat
• engineering scaling
• reliability analysis methods

6
RD for Chamber Technology is a Grand Challenge
not only because of the multi-function,
multi-physics, multi-engineering requirements and
issues but also because of the complex and unique
thermo-magneto-vacu-tritu-nuclear environment of
fusion

• Neutrons (fluence, spectrum, spatial and temporal
  gradients)
• - Radiation Effects (at relevant temperatures,
  stresses, and loading)
• - Bulk Heating
• - Tritium Production
• - Activation and Decay Heat
• Heat Sources (magnitude, gradient)
• - Bulk (from neutrons)
• - Surface (from particles and radiation)
• Particle Flux (energy, density, gradients)
• Magnetic Field (3-component with gradients)
• - Steady Field
• - Time-Varying Field
• Mechanical Forces
• - Normal (steady, cyclic)
• - Off-Normal (pulsed)
• Thermal/Chemical/Mechanical/Electrical/Magnetic/Nu
  clear Interactions
• and Synergistic Effects
• Combined environmental loading conditions
• Interactions among physical elements of
  components

 The kind of training needed to perform research
and engineering within this highly constrained
fusion chamber system takes many years of
education and experience.
7
Technology Programs are Highly Interrelated and
Interactive (Take as an analogy a three-legged
stool PFC, Chamber Tech, and Materials) (Many
Other 3-legged stool examples can be shown with
other parts of the fusion program, e.g. with
Safety and Design Studies Programs)
P
S
- Primary role for resolving issue,
- Supporting role in resolving issue
8
Why Chamber Technology Research Now?

• Why Now?!
• It is not just needed now!
• It was needed 30 years ago!
• It was started 30 years ago!
• It would have been impossible for the fusion
  program to make the progress we have made without
  Chamber Technology Research over the past 30
  years.
• No Credible plans for future fusion development
  are possible without Chamber Technology Research
  NOW.
• One way to understand why now is to learn how
  Chamber Technology Research was crucial in making
  progress over the past 30 years.

9
Since the Early 1970s, Chamber Technology
Research has had a Fundamental and Major Impact
on

• The Direction and Emphasis of Plasma Physics RD
• The Direction and Emphasis of other Fusion
  Technology Programs
• Identifying and Resolving Critical Issues in
  Fusion, many of which are Go, No-Go issues
• Shaping our vision today of a burning plasma
  device and fusion power plant

This impact is illustrated by some historical
examples given in a separate handout.
10
Remaining Critical RD Issues for Chamber
Technology (FNT)

• Remaining Engineering Feasibility Issues, e.g.
• feasibility, reliability and MHD crack tolerance
  of electric insulators
• tritium permeation barriers and tritium control
• tritium extraction and inventory in the
  solid/liquid breeders
• thermomechanics interactions of material systems
• materials interactions and compatibility
• synergistic effects and response to transients
• D-T fuel cycle tritium self-sufficiency in a
  practical systemdepends on many physics and
  engineering parameters/details e.g. fractional
  burn-up in plasma, tritium inventories, FW
  thickness, penetrations, passive coils, and many
  more variables. A related issue is how to supply
  Tritium for burning plasma experiments, such as
  ITER.
• Reliability/Maintainability/Availability failure
  modes, effects, and rates in blankets and PFCs
  under nuclear/thermal/mechanical/electrical/
  magnetic/integrated loadings with high
  temperature and stress gradients. Maintainability
  with acceptable shutdown time.
• Lifetime of blanket, PFC, and other FNT components

11
NOW is the time to develop tritium breeding
blanket for extended ITER Operation and beyond

• Tritium Supply considerations are a critical
  factor in Fusion Energy Development
• Experimental DT Devices for Fusion Energy
  Development Will Need a Tritium Breeding Blanket
• The world maximum tritium supply (from CANDU)
  over the next 40 years is 27 kg. This tritium
  decays at 5.47 per year. Cost is high
  (30M-200M/kg)
• A DT facility with 1000 MW fusion power burns
  tritium at a rate of 55.8 kg/yr. Large power DT
  facilities must breed their own tritium.
• (It is ironic that our major problem is tritium
  fuel supply, while the fundamental premise of
  Fusion is an inexhaustible energy source)
• This is why testing of breeding blanket module is
  Planned in ITER from Day 1 of Operation (2013),
  since ITER can not run in the extended phase
  without breeding
• The Fusion Program needs to show that tritium
  self sufficiency in a practical engineering
  system is indeed attainable in a real fusion
  device. This is a challenge, involves gt 20
  physics, engineering, and material variables.

12
The Lack of Adequate Tritium Supply and the Need
for Tritium Breeding Blanket are Already Having a
Major Impact NOW on ITER Operational Plans and
Fusion Energy Development Plans
See calculation assumptions in Table S/Z

• Without a tritium breeding capability, ITER
  cannot run in an extended phase.
• Large power DT facilities must breed their own
  tritium

• Breeding Blanket must be developed NOW - We
  cannot wait very long for blanket development
  even if we want to delay DEMO

13
We must proceed quickly to participate in ITER
Technology Testing Program

• ITER was conceived not only as a burning plasma
  experiment but also as an experiment to test
  fusion technologies in a real fusion environment.
  
• The Chamber Technology Program has a leading role
  in both the basic device and the blanket test
  module missions.
• ITER can provide important functional and
  screening tests for vital tritium breeding
  technologies

Notion It doesnt make sense to pay billions to
build ITER, and not spend millions to utilize
ITER to acquire key technology data and experience
14
ITER Operational Plan Calls for Testing Breeding
Blankets from Day 1 of Operation
15
TBM Roll Back from ITER 1st Plasma Shows CT RD
must be accelerated now for TBM Selection in 2005
EU schedule for Helium-Cooled Pebble Bed TBM (1
of 4 TBMs Planned)
ITER First Plasma
a final decision on blanket test modules
selection by 2005 in order to initiate design,
fabrication and out-of-pile testing
(Reference S. Malang, L.V. Boccaccini, ANNEX 2,
"EFDA Technology Workprogramme 2002 Field
Tritium Breeding and Materials 2002 activities-
Task Area Breeding Blanket (HCPB), Sep. 2000)
16
Reliability/Maintainability/Availability is one
of the remaining Grand Challenges to Fusion
Energy Development. Chamber Technology RD is
necessary to meet this Grand Challenge.
Need High Power Density/Physics-Technology
Partnership
- High-Performance Plasma
Need Low
-
- Chamber Technology Capabilities
Failure Rate



replacement cost
M
O
i
C


COE
h



M
P
Availability
th
fusion
Energy
Need High Temp.
Multiplication
Energy Extraction
Need High Availability / Simpler Technological
and Material Constraints


Need Low Failure Rate
- Innovative Chamber Technology


Need Short Maintenance Time
- Simple Configuration Confinement
- Easier to Maintain Chamber Technology
17
The reliability requirements on the Blanket/FW
(in current confinement concepts that have long
MTTR gt 1 week) are most challenging and pose
critical concerns. These must be seriously
addressed as an integral part of the RD pathway
to DEMO. Impact on ITER is predicted to be
serious. It is a DRIVER for CTF.
The Chamber Technology Program NOW is leading
the way to resolving this challenge.
A Expected with extensive RD (based on mature
technology and no fusion-specific failure modes
C Potential improvements with aggressive RD
18
Why do research now on Chamber Technology?

• Utilization of ITER technology testing
  environment
• Develop needed tritium breeding and recovery
  technologies for burning plasma experiments and
  to demonstrate fusion fuel self-sufficiency
• Impact on current and future physics program
• Vital Interactions with other technology programs
  
• Key predictive capabilities needed by all
  programs
• Access to the broader international technology
  research / data though existing collaborations
• Training young technology researchers that will
  be running ITER and CTF experiments in 10 years
• Tough technology problems require long testing
  and development times e.g. Reliability Growth

19
CT Plans for FY 04/05
A Chamber Technology Program is Essential to the
New Presidential Initiatives to join ITER and
Implement an Energy-Based Policy for Fusion
The Chamber Technology Community is ready to move
to a new emphasis 1. Re-Start ITER Test Blanket
Module Program 2. Support ITER Basic Device in
the FNT area 3. Continue research on Advanced
Chamber Configurations with re-adjusted scope 4.
Maintain vital efforts to advance fundamental
Predictive Capabilities and tools needed by other
Fusion Programs 5. FNT Experimental Techniques
and testing to support the energy development
plans
Learn from proven successful APEX Features 1)
Multidisciplinary, multi-institution integrated
TEAM 2) Close Coupling to the Plasma Community 3)
Direct Participation of Scientists from
Materials, PFC, Safety, and AD Programs 4) Direct
Coupling to IFE CT Community 5) Direct
participation with International programs 6)
Encourage Innovation
Note Balance among these elements in a
constrained budget will be derived from community
deliberations.
20
Chamber Technology Plan for FY 04/05
CT Plans for FY 04/05 (contd)
1. Blanket Test Module Program (for ITER and
other devices)

• Lead US community to evaluate blanket options for
  DEMO, evaluate RD results for key issues to
  select TWO Primary Blanket Concepts for testing
  in ITER (must reach a decision by 2005). This
  effort will also involve interactions with EU,
  Japan, and China for coordinated, cost effective
  efforts. In addition to the CT community, this
  effort will involve participation by many US
  programs (e.g. Materials, Safety, PFC, and
  Advanced Design Studies Programs and industry)
• Perform concurrently RD on the most critical
  issues required to make prudent selection by 2005
  (e.g. self-healing coatings and other types of
  MHD insulators, tritium permeation barriers, SiC
  inserts, solid breeder/multiplier/structure/coolan
  t interactions)

21
Blanket Test Module Program (contd)

• Enhance and focus current international
  collaborative RD to provide data to ITER Blanket
  Test Module Selection
• a) Thermomechanics material interactions for
  SB/multiplier/structure/coolant (ongoing under
  IEA)
• b) Enhanced heat transfer techniques for molten
  salts to determine if there is a temperature
  window with ferritic steel structure and/or
  advanced high-temperature ferritic steel (ongoing
  under JUPITER-II)
• Participate in international unit cell
  experiment in fission reactors (tritium release
  and breeder/multiplier/structure/purge
  interactions)
• Develop Engineering Scaling and design blanket
  test articles in the ITER environment for the
  blanket concepts selected for testing in ITER

22
CT Plans for FY 04/05 (contd)

• 2. FNT Support for the ITER Basic Device
• As ITER moves toward construction it will need
  more accurate predictions in the nuclear area
• e.g. computation of radiation field,
  radiation shielding, nuclear heating,
  penetrations, materials radiation damage, dose
  to insulators in superconducting magnets, decay
  heat, radwaste, maintenance dose, tritium fuel
  cycle, tritium permeation and inventories, basic
  device non- breeding blanket issues and
  performance
• Help resolve remaining issues in ITER design e.g

- flexibility in non-breeding blanket design to
ensure feasibility for change to breeding blanket
in the extended phase
- providing for auxiliary and ancillary equipment
to support the ITER Blanket test module program
- diagnostics to monitor in-situ FW/Blanket
operating conditions
23
CT Plans for FY 04/05 (contd)

• 3. Advanced Chamber Configurations and High
  Pay-Off Concepts
• (Emphasis on Innovation and Engineering Sciences
  - Similar to Plasma Confinement Alternate
  Concepts and Configuration Optimization)
• Thin liquid wall concepts RD on critical issues
  to evaluate feasibility, attractiveness
  (including plasma-chamber interactions)
• Provide thermofluid MHD and design support for
  the NSTX liquid-surface test module (joint
  activity between PFC/ALPS and Chamber Technology)
  and MHD channel flow tests
• Evaluate the potential of advanced blanket
  concepts with attractive combinations of
  materials and configurations.
• This activity will be aimed at GEN-II in US DEMO
  (see 35-yr plan) and possibly hydrogen
  production, but successful results may have
  profound near-term impact on the fusion program

24
CT Plans for FY 04/05 (contd)
4. Fundamental Predictive Capabilities (Computatio
nal Models and Codes and Tools Needed by Other
Key Fusion Programs, e.g. Safety, Materials, PFC,
Advanced Design Studies)

• Heat Transfer/Fluid Mechanics/MHD
• Radioactivity and Decay Heat
• Tritium Transport/Recovery/Control, Tritium Fuel
  Cycle Dynamics
• Reliability and Availability
• Neutronics and Neutron-Material Interactions

5. FNT Experimental Techniques and Diagnostics

• Develop experimental techniques and engineering
  scaling for testing Chamber Technology on fusion
  devices
• Develop diagnostic techniques for operation in
  the magneto-nuclear environment of fusion devices
  (ITER, CTF, etc.)
• Evolve technical and programmatic strategies for
  Fusion Nuclear Technology testing and development
  on ITER, CTF, and other devices leading to DEMO
  (support the 35-yr Plan)

25
Consequences of Terminating Chamber Technology
Program

• Loss of Credibility to the fusion program and to
  any fusion energy plan
• It undermines the initiative to rejoin ITER
• It makes the 35-yr US Plan dead on arrival
• At odds with the Presidents New Policy for
  Fusion
• Demoralizing to fusions advocates
• Heartening to fusions critics
• Confusing and frustrating message to the
  International Fusion Programs
• Devastating consequences to the US Fusion
  Programs ability to make progress

26
Consequences of Terminating Chamber Technology
Program (contd)

• Moving forward with fusion requires many diverse
  skills in Chamber Technology.
• After the 1996 restructuring, only a bare
  minimum of critical skills remain skills that
  took 30 years to develop.
• Termination of the CT Program will set fusion
  energy back by decades.
• Loss of FNT headlights Enormous risk that near
  term fusion research may not ultimately bear the
  fruit of a practical fusion energy source.

27
Specific and Immediate Consequences

• No participation in ITER test program or
  possibility to test US blanket modules. Loss of
  ability to influence ITER decisions on the test
  program, scheduled to be finalized in 2005.
• Loss of capability for timely demonstration of
  tritium self sufficiency - the fundamental
  premise of fusion as an inexhaustible energy
  source.
• Loss of vital expertise needed to design and test
  in ITER, CTF, and DEMO.
• Great harm to important elements of the US fusion
  technology program. CT Research, Materials,
  Safety, and Advanced Design studies interact very
  strongly.
• How can we do safety analysis without
  radioactivity calculations and technologies for
  tritium containment?
• How do we develop structural materials for the
  blanket if we do not know what the blanket is?
• How do we predict MHD induced motion of lithium
  in DiMES/DIIID during plasma operation?
• Loss of critical interaction with the plasma
  community to solve the plasma-chamber interface
  issues and to provide innovative Chamber
  solutions to improve plasma performance.

28
Specific and Immediate Consequences (Cont.)

• No research on innovative technology ideas that
  may have the most significant impact on the
  attractiveness of fusion energy or hydrogen
  producing systems.
• Loss of access to foreign research/data from
  existing CT international collaborations. (also
  loss of funding from Japan)
• Loss of investment in unique new experimental
  facilities recently constructed.
• Drastic reduction in university involvement and
  serious impact on many Professors, Fusion
  Researchers and PhD students
• Loss of training for the seed of the future
  graduate students and young researchers. CT
  Research provides training and development of
  skills for people that go on to lead other
  programs. The head of the US Safety Program, the
  Head of the Vacuum Vessel Division in KSTAR, and
  the Head of the PFC components in Europe and
  ITER, for example, were all students trained in
  the US Chamber Technology Research Program. Many
  fusion leaders and university professors in the
  US, Europe and Japan were trained as part of the
  US CT Research Program.
• Loss of current CT leadership at a time when the
  program needs more technology emphasis as we move
  toward ITER, CTF, and demonstration.