Material System Design Studies of High Temperature Gas-Cooled Solid

Breeder Blanket Module

A.Hasegawa (Tohoku Univ.)

A.Shimizu, T.Yokomine (Kyushu Univ.)

ITER TBM Project Meeting

UCLA, USA2/23-25, 2004

Summary of Current Status for TBMs

WSG1 (Helium-cooled/Be (F/M steel, SiC/SiC) Blankets- TBM of F/M steel has been proposed- SiC/SiC Blaket: DEMO Design Study (DREAM), SiC/SiC Material Tests, Specimen

Irradiation Test, Research on Cooling, Some of them by JUPITER-IIWSG2 (Helium-cooled Lithium Lead (F/M steel, SiC/SiC) Blankets- Demo Design Study (Vector), Many activities existed. Interesting aloso for ICF blan

ket, Proposal will be madeWSG3 (Water-Cooled Ceramic/Be (F/M steel) Blankets- Demo Design Study, R&Ds on corrosion, heat transfer, material irradiation being c

onductedWSG4 (Self-Cooled Lithium (V) Blankets- Network activities in Universities/NIFS, Evaluation of Russian Design, Going to des

ign Japanese Blanket, Planning of R&D, Researches on vanadium alloy, coating, impurity control, tritium recovery, cooling, some of them by JUPITER-II and by IFMIF.

WSG5 (Self-Cooled Molten Salt Blankets)- Network activities in Universities/NIFS, Demo Design Sudy of FFHR, R&

Ds on many parts (redox control, cooling, tritium recovery, …) some of them by JUPITER-II, by TNT-loop, planning of R&D for TBM.

Expected ParticipantsDpt. of Quantum Science and Energy Engineering

Tohoku University

Structure materials : Hasegawa (Tohoku Univ.)

Kohyama( Kyoto Univ.)

Solid breeding materials : Enoeda (JAERI)

Shikama( Tohoku Univ.)

Neutron multiplier : TBD (JAERI)

Shibayama(Hokkaido Univ.)

Thermomechanis : Shimizu (Kyushu Univ.)

System design : Konishi (Kyoto Univ.)

Tritium recovery system : TBDThe advanced Helium cooled blankets will be studied by collaborative works by universities and JAERI.

Current interests in various blankets by parties

Parties JA EU US RF China Korea

PB/He ○ ○ ○ ○ ○ ○

LiPb/He △ ○ ○ ○ ○ ○

Pb/Water ○ ○

Li/V ○ ○ ○ ○ ○

Salts ○ ○

Roadmap for Materials and Blanket Development in Japan

Materials and Blanket System Development

Reference Material (RAFM) and System

Design Construction Operation

ITER

Power Generation Plant

Irradiation Test, Materials Qualification and System Performance TestIFMIF

1st commercial plant Design

(Staged construction and operation)

(Licencing) (Blanket test)

Blanket Module Test

Approximate calendar year 2015 2020 2030 2040

Advanced Materials (V-alloy, Flibe, SiC/SiC --) and System

Reference Blanket (Mostly JAERI responsibility)

Advanced option (Mostly NIFS/University responsibility)

modification

Back Ground of this ActivitiesDpt. of Quantum Science and Energy Engineering

Tohoku University

●Based on irradiation behavior of SiC, advanced SiC/SiC composites were developed using stoichiometric SiC fibers.

・ increase radiation resistance using advance fiber

no mechanical degradation up to 10dpa at 800C

high size stability

Recent achievement of SiC/SiC composites -1-

Back Ground of this ActivitiesDpt. of Quantum Science and Energy Engineering

Tohoku University

●Development of new matrix processing, NITE, enabled to increase matrix density.

The lower porosity and near theoretical density realized

high hermeticity and good thermal conductivity of SiC/SiC composites. Joining between SiC/SiC composites was also 　 successful by the NITE process.

It is almost ready to fabricate complex shape structure made of SiC/SiC composite such as gas cooling blanket .

To start design activity of the blanket system, the technical issues will be discussed in this working group.

Recent achievement of SiC/SiC composites -2-

NITE: Nano-Infiltration Transient Eutectic Phase Process• Dense and robust structures (cf. PIP, CVI, …)• Fairly high thermal conductivity• Chemical stability• Thin plate production, surface smoothness, potential gas

tightness• Applicability of existing net-shaping techniques• Low production cost

What is NITE Process ?

Matrix slurry;SiC + Additives

Fabrics

Infiltration of slurry DryingHot pressing

Shape-Variability of NITE Composites

Tube: 31-33 x 60.0mmThin Plate: 195 x 195 x 2.0mm

Thick Block: 97 x 97 x 70mm Combustor Liner

Kohyama et al.,(2002)

Qualification of these composite is in progress under collaboration with high temperature gas turbine program.

Hino et al.,(2003)

Monolithic SiC by NITE

SiC/SiC by NITESiC/SiC by NITE

#1 Pilot SiC/SiC by NITE (Ube )

Permeability of NITE Composites 　 at RT

Research Area for High Temperature Gas Blanket System

Dpt. of Quantum Science and Energy Engineering

Tohoku University

●Study on blanket system design for high temperature gas-cooling system is started 　 in Japan to realize high efficiency energy source of fusion power plant. Design and feasibility studies base on the following fields will be discussed in this working group.

　　　 Material development, Thermomechanics,

　　　 Tritium recovery system

Material Design for High Temperature Blanket System

Structural Materials, Sold Breeding Materials,

Neutron Multiplier Materials

Bulk-flow type （ DREAM ） Channel type （ DEMO, HCPB ）

Advanced Gas Cooling System

There are two types of gas cooling system

1) Bulk-flow type : one major gas loop

2) Channel type : two major gas loops

( T purge gas loop + He gas cooling loop)

Dpt. of Quantum Science and Energy Engineering

Tohoku University

Bulk-Flow Type

Heat EfficiencyBlanket

Heat Exchanger

Tritium Recovery System

＞ 900℃

DREAM

Tritium Recovery Efficiency

High

High

Channel type

Blanket Cooling LoopTritium Recovery

Loop＞ 900℃

＞ 1000℃

High Heat EfficiencyHigh Tritium

Recovery Efficiency

Key issues of this Blanket SystemDpt. of Quantum Science and Energy Engineering

Tohoku University

●To realize high energy efficiency of blanket, higher temperature (900 )℃ 　 outlet-gas is required.

●New breeding material which has higher temperature resistance is needed to utilize high temperature capability of SiC/SiC composite.

ex. coating or dendrite structure breeding materials

●Upper limit of current solid breeding materials : < 　 900C

●High temperature performance of solid breeding materials such as resistance to sintering and creep deformation become important.

●To obtain higher temperature outlet gas, temperature of wall and solid breeder becomes much higher than the gas temperature.

SumaryDpt. of Quantum Science and Energy Engineering

Tohoku University

●In the high temperature gas cooling system, many material and system issues remain and some break-through of high temperature resistance of breeding material are required.

●Japan proposes to include testing of SiC/SiC composite and high temperature blanket concepts in TBMs.

●Considering about limited resources and timeframe, this advanced blanket module is expected to join later phase of ITER.

TitleDpt. of Quantum Science and Energy Engineering

Tohoku University