1. Overview of the US ITER Test Blanket Module (TBM) Technical Plan
Mohamed Abdou
for the US ITER TBM Team
Presented at 17th ANS TOFE, Albuquerque, NM
November 15, 2006

2. Testing Blankets is an integral part of ITER planning - all Parties view TBM testing as key motivation for ITER
US ITER TBM
“Day 1” H-H Phase TBM Testing is required by ITER for:
Optimization of plasma control in the presence of Ferritic Steel TBMs
Qualification of remote handling procedures
Qualification and licensing of the experimental TBM designs and operation before D-T phase
ITER Schedule 1st 10 yrs
ITER has allocated 3 ITER equatorial ports (1.75 x 2.2 m2) to TBM testing
Test planning is managed by TBWG which consists of:
Representatives of the seven ITER Parties
Representatives of the ITER International Team
Ground rules for port allocation, space usage, and collaboration are being negotiated in a high-level Ad-Hoc committee created by IPC with government level representatives

3. US TBM Technical Plan and Cost Estimates have been developed and favorably reviewed (ready for implementation)
US ITER TBM
The US Fusion Community completed the development of a “Technical Plan and Cost Estimate” for the US TBM. It presents detailed technical options and credible cost estimates for consideration by the US Government. (It follows the US ITER Project Methodology.)
The effort was requested by DOE (Gene Nardella) in August 2005.
The effort was performed by the US ITER TBM Team, which includes experts from the Plasma Chamber, Materials, Safety, Plasma Facing Components, and Tritium programs. Costing and project management professionals from Oak Ridge National Laboratory and experts from various universities, national laboratories, and industry also assisted in developing the cost estimates and schedule. Consultation with TBM teams in other countries was very helpful as well.
DOE External Review was conducted August 15-16, All Reviews were very positive.

4. Pipes to TCWS and Tritium Building
US TBM Program Mission – Utilize ITER environment for invaluable technology testing
US ITER TBM
The principal mission of the US ITER Test Blanket Module (TBM) Program is to develop, deploy, and operate ITER TBM experiments that provide unique experimental data on, and operational experience with, the integrated function of US blanket components and materials in a true fusion plasma-magnetic-nuclear-thermal-chemical environment.
TBM testing requires a whole TBM system (module + ancillary equipment)
Specific TBM Test Objectives include:
Validation of structural response under combined thermal, mechanical, and EM loads
Validation of tritium breeding predictions
Validation of tritium recovery process efficiency, tritium control and inventories
Validation of thermonuclear and thermofluid MHD predictions in strongly heterogeneous blanket and first wall structures with volumetric heat sources
Demonstration and understanding of integral performance of blanket components and material systems
Experience with design, fabrication, installation and maintenance of prototypical blanket and first wall structures
Pipes to TCWS and Tritium Building
VV Port Extension
PbLi loop
Transporter
Container
TBM Port Frame
TBM
Bio-shield
Example – US DCLL TBM and support systems in the port cell area (He systems in TCWS not shown)

5. HCCB TBM sub-module (710  389  510 mm)
Baseline strategy proposes different levels of participation for two US TBM concepts
US ITER TBM
DCLL TBM Module (1660 x 484 x 410 mm)
After extensive effort two blanket concepts that have substantially different feasibility issues were selected:
Poloidal flow
PbLi Channel
1. The Dual-Coolant PbLi Liquid Breeder Blanket (DCLL) concept with self-cooled PbLi breeding zone and flow channel inserts (FCIs) as MHD and thermal insulator.
Innovative concept (favored by US PC and ARIES, and EU – DEMO) that provides “pathway” to higher outlet temperature/higher thermal efficiency while using ferritic steel .
He-cooled RAFS FW
SiC FCI
US lead role in collaboration with other parties. Plan an independent TBM that will occupy half an ITER test port.
2. The Helium-Cooled Solid Breeder Blanket (HCCB) concept with ferritic steel structure and beryllium neutron multiplier, but without an independent TBM.
HCCB TBM sub-module (710  389  510 mm)
Ceramic breeder pebbles
ALL parties are interested. HCCB is the most likely candidate for near-term breeding blankets, e.g. in ITER extended phase.
Supporting partnership with other parties with shared ancillary equipment. With modest investment in HCCB, US will gain access to large international program,
Be Pebbles
He-cooled RAFS FW
Contribute submodule test articles that focus on particular technical issues.

6. US DCLL TBM Module (1660 x 484 x 410 mm)
Main Features of the DCLL “Pathway” to higher thermal performance with ferritic steel
US ITER TBM
US DCLL TBM Module (1660 x 484 x 410 mm)
RAFS first wall and structure cooled with high pressure (8MPa) helium operating at C (flexible) in ITER (higher in DEMO)
Breeding zone is self-cooled PbLi operating at ( C) in ITER (higher in DEMO)
Structure and Breeding zone separated by SiC flow channel inserts (FCI) ~5mm thick
Provide thermal insulation to decouple PbLi bulk flow temperature from RAFS walls
Provide electrical insulation to reduce MHD pressure drop in the flowing liquid metal
He Coolant
Outlet Pipe
Poloidal flow
PbLi Channel
Toroidal flow He-cooled First Wall
SiC FCI
Concept: PbLi exit temperature can be significantly higher than the operating temperature of the steel structure  High Efficiency

7. HCCB Joint Partnership
US ITER TBM
Preliminary discussions occurred among US, Japan, and Korea about a possible partnership on HCCB.
KO Submodule
JA Submodule
The proposed US HCCB sub-module will occupy 1/3 of an ITER horizontal half-port
US Submodule
The back plate coolant supply and collection manifold assembly, incorporating various penetration pipes, flexible supports, and keyways, should be collaboratively designed by partner Parties. A “Lead Party” takes responsibility for fabrication of the back plate and integration of the three sub modules.

8. US TBM Deliverables: Hardware Ready-to-Ship to ITER by Mar. 31, 2015:
US ITER TBM
DCLL
1.6 m
HCCB
5 m
A full size, vertical half-port, DCLL test blanket module;
A 1/3 size, horizontal half-port HCCB test blanket submodule integrated with a host Party’s test module
Example DCLL He loops in the TCWS Vault
Primary and secondary DCLL helium coolant flow loops
A one-third share of the HCCB ancillary systems, including He coolant and purge
2 m
A DCLL PbLi coolant flow loop
Specifications for tritium processing system
Example DCLL PbLi loop in port cell transporter container

9. Basic US Technical Plan Flow
US ITER TBM
Products:
Qualified Design
- Qualified Fab. Technology
- Verified Simulation Cap.
Progression from basic R&D through single and multiple effects tests (including small and medium scale mockup testing) to fabrication and testing of scaled-mockups and full scale Prototype
Basic Properties
Models & Theory
Single/Multiple Effects Testing
Simulation Codes
Partially-Integrated Mockup Testing
Data/Codes Integration and Benchmarking
Evolution of verified predictive capability in concert with experimental program
Complete and coupled computer-aided engineering design and safety analyses

10. R&D tasks directly support TBM design, safety, qualification, and/or operation requirements
US ITER TBM
The ITER TBM qualification and licensing process will be arduous
TBMs must not interfere with operation, availability, or safety of ITER
acceptance will demand testing in the H-H phase, for which we need to begin preparing now
DCLL and HCCB Technical Issues
Design, fabrication and qualification of structures with RAFS
Integrated response of complex geometry, highly-heterogeneous TBM mockups in ITER-like conditions
Robust diagnostics compatible with ITER operating conditions and TBM design and materials
Tritium removal, release and permeation
He flow distribution and heat transfer characteristics
DCLL only Technical Issues
Coupled impact of FCI thermal, electrical, and structure properties and design on MHD velocity profiles and operating temperature
Fabrication of SiC with desired FCI properties
Compatibility of PbLi with materials and reactivity with water
HCCB only Technical Issues
Thermomechanical behavior of pebble beds and impact on operating temperature

11. FCI/SiC Devel. & Fabrication
Many R&D tasks are highly interactive, and collectively, they provide information critical to design, procurement specifications, qualification/acceptance tests, and definition of operating conditions
US ITER TBM
Example:
Flow Channel Insert (FCI) in DCLL
Flow Channel Insert Function
Decouple PbLi & FS
Thermal insulation
Electric insulation
Low primary stress
Robust to thermal stress - T ~200C
Thermofluid MHD
Structural Analysis
ITER TBM
Effectiveness of FCI as
electric/thermal insulator
MHD pressure drop and
flow distribution
MHD flow and FCI
property effects on T
FCI stresses
FCI deformations
FCI/SiC Devel. & Fabrication
Tailoring k and 
k(T), (T)
Irradiation effect
Fabrication issues
ITER DT
MHD Experiments
Manifolds
3D FCI features
ITER DT: Max stress<45 MPa
UCLA Manifold Flow distribution Experiment (~1m length)

12. RAFS Fabrication R&D determines detailed material and fabrication specifications
US ITER TBM
R&D needed for:
Input to design analyses
ITER Structural Design Criteria
TBM Technical Specification Doc.
Vendor Bid Packages for prototype and first TBM
Basic Properties
Single and Multiple Effects Testing
Partially-Integrated Mockup Testing
Material alloy specification
Fabrication procedures
Properties - base metal & joints
Tolerances
Small/Med mockups
- Irradiation,
- Corrosion,
- Thermal/stress
Final Design
TBM Fabrication
Acceptance Tests
Init R&D
Oct
FabRoute
Dec
BidPack
Aug FY

13. R&D activities underway in several critical areas for US TBMs
US ITER TBM
Current R&D efforts:
DCLL MHD experiments and simulation – manifolds and FCI function
SiC materials development and property measurements for FCI
PbLi/SiC/FS compatibility and LM ingress tests
Pebble bed thermomechanics experiments and simulations
Initial contacts with US industry regarding initiating RAFS fabrication development R&D in FY07
Possible FCI Material – Low Conductivity SiC Foam with dense sealing layer from ULTRAMET Tested with LM at UCLA
PbLi/SiC/Alloy Capsule Compatibility Tests from ORNL
DCLL MHD numerical simulation of PbLi velocity through a three-channels dividing manifold: left: fully developed MHD flow characteristics at each channel; right: PbLi velocity evolution from the manifold inlet to three parallel channels

14. Numerical Simulations of Manifoldx y z B 25 50
100 20
250
Slit
Duct
Velocity profiles from inlet to outlet
UCLA’s Experimental Geometry of Manifold
Current distribution at the outlet shows that the flows here is fully developed
The center channel has flow rate 11.8% above the uniform flow, and the side channels have -5.% below the uniform flow.
Velocity vector shows M Shape Velocity, and Vortex Parallel to the magnetic field

15. Heat Transfer in DCLL blanket is strongly affected by fluid flow phenomena, where MHD plays a major role
US ITER TBM
Model Development  Numerical Simulations  Design A B C D
Formation of high-velocity near-wall jets
B. 2-D MHD turbulence in flows with M-type velocity profile
C. Reduction of turbulence via Joule dissipation
D. Natural/mixed convection
E. Strong effects of MHD flows and FCI properties on heat transfer g
=5 E
DEMO
=100
=500

16. VTBM Integrated Data/multi-code multi-physics modeling activities, or Virtual TBM, is key for ITER TBM R&D activity.
US ITER TBM
The design of a complex system like the ITER TBM requires an exhaustive CAE effort encompassing multiple simulation codes supporting multi-physics modeling.
Temperature in solid domain
Stress and Strain in solid domain
CAD model of structure
CAD Model Input
CAD to Analysis Intermediaries
Fix CAD model
Neutronics
Electromagnetics
Thermo Fluid
Mass Transfer
Structural

17. R&D, Design, Fabrication and Qualification Schedules are linked by Yearly Milestones
US ITER TBM
Key early design decisions, TSD 1st Draft
Approve Prototype Fabrication, complete structural design criteria
Approve 1st Module Fabrication, Final TSD
Key Project Milestones
All activities tied to Milestones
The critical path is discerned based on inter-dependencies of tasks
Information from R&D is available in time to support design, fabrication and qualification

18. Testing Tritium Breeding Blankets in ITER is ESSENTIAL to show that fusion has a potential as an energy source
US ITER TBM
ITER TBM will address the following central questions about D-T fusion:
Is there a practical blanket compatible with the plasma that can achieve tritium self sufficiency? (Is the D-T cycle practical?)
Can high-grade heat extraction (high efficiency) be realized in the fusion environment (and reliably in a system inside the plasma vacuum vessel)?
Without TBM, hence ignoring power extraction and tritium self-sufficiency, the US strategy for the long term will have a very big hole – invalidating any mid- to long-term strategy to meet an energy goal.
The critics of fusion argue that "the time to realize fusion is 40 years away and expanding". Not participating in ITER TBM will guarantee that these critiques are right.
TBMs are critical to solving the Tritium Supply Issue for continued fusion development
Successful ITER will exhaust most of the world supply of tritium
A fusion reactor consumes tritium at a rate ~100x more than a fission production reactor can produce
ITER extended performance phase and any future long pulse burning plasma will need tritium breeding technology

19. Summary A technical plan for US ITER TBM has been developed.
The US extensive experience, pioneering development of FNT, and in-depth studies of engineering testing in fusion facilities over the past 35 years allowed the development of a credible and effective technical plan.
The combined efforts of the community’s technical experts and costing and management professionals enabled a reasonably accurate cost estimate which is much more detailed and more comprehensive than that of any other ITER Party.
Analysis of the current situation (ITER, international, domestic) demands strong US participation in ITER Blanket Testing.