Scope and Objectives
(1) Tritium technology related continuous bred tritium recovery and inventory evaluation
For DEMO design, it is extremely important to develop and validate the technology for the tritium continuous processing and accountancy. This system shall handle the tokamak exhaust and the flow of tritium extracted from the breeding blanket. The main purposes are: 1) Development of Tokamak Exhaust Processing (TEP) design and corresponding technology focusing on the common development of analytical tools and analysis systems for tritium accountancy. For the most urgent needs in terms of analytics development an associated hardware development will be assessed and carried out, and 2) Set-up of detailed models in the fuel cycle simulator. In addition, 3) Analysis of plasma wall interaction using JET ILW and JET DT samples for evaluation of tritium inventory and tritium recovery.
(2) Development structural material for fusion DEMO in-vessel components
The final objective of this R&D is to develop the technical bases for DEMO structural design criteria for in-vessel components, i.e. Breeder Blanket and Divertor and respective material Annexes for RAFM steels, Cu-alloys and W-based materials. Probability-baseddesign methodologies are considered in parallel to the conventional deterministic design method. An irradiation database and respective methodologies to best estimate the fusion neutron irradiation effects shall be developed considering both design approaches.
(3) Neutron irradiation experiments of Breeding Functional Materials (BFMs)
The in-pile experiments are essential to assess the BFMs capability to produce and release tritium. The main purpose is to perform new neutron irradiation campaign of the advanced BFMs for the establishment of the DEMO design database of initial irradiation behavior. This must be done conducting evaluation of initial neutron irradiation behavior via in-situ tritium release experiments and also post-irradiation experiments (PIEs) of irradiated BFMs.
(4) Development of material corrosion data base
Developments of material corrosion handbook and activated corrosion product (ACP) evaluation model for fusion in-vessel components are addressed as common R&D items for both water-cooling system and liquid Pb-Li breeding system. For those purposes, reduced-activation ferritic/martensitic (RAFM) steel and its variants are considered as the primary materials for both water and liquid Pb-Li metal systems. Cu-alloys are also considered as one of diverter material options for the water-cooling system.
The DEMO R&D Activities aim at establishing a common basis for a DEMO design from the technology point of view. The following five R&D areas have been identified to be performed during the BA period.
T1: R&D on SiCf/SiC Composites
Deliverables (Goal): development of material database of advanced SiCf/SiC for DEMO relevant, physical/thermal/mechanical properties, assessment of the compatibility between SiCf/SiC and liquid lead lithium, investigations of the self-coolant/ dual-coolant liquid breeder blanket system and of the dynamic irradiation effects on transportation properties of SiC and SiCf/SiC, etc.
T2: R&D on Tritium Technology
Deliverables (Goal): development of tritium technologies towards the DEMO plant (continuous operation), preparation of Tritium Handling Equipment, development of Tritium Accountancy Technology, Basic tritium safety research, Tritium durability test, etc.
Also, analysis of tile and dust of JET ITER Like Wall (ILW) was newly proposed and added to the scope of T2 from 2014 to 2019.
T3: R&D on Materials Engineering for DEMO Blanket
Deliverables (Goal): establishment of sound engineering bases on materials database, modelling/simulation/prediction methods of materials behaviour and design methodology, measurement of the fracture/rupture properties of the irradiated materials, development of data bases for DEMO design criteria and licensing, etc.
T4: R&D on Advanced Neutron Multiplier for DEMO Blanket
Deliverables (Goal): development of Advanced Neutron Multiplier with low swelling and high stability at high temperature, the development of a manufacturing technology, preparation of test facility, etc.
T5: R&D on Advanced Tritium Breeders for DEMO Blanket
Deliverables (Goal): development of advanced tritium breeders with higher stability at high temperatures and lithium recycle capability, preparation of test equipment, the development of fabrication technologies of advanced breeder pebbles, characterisation and reprocessing studies of the developed breeder materials, etc.