Chair(s): |
Paul SCHUURMANS, Belgium |
Secretary: |
Gabriele GRASSI (gabriele.grassi@oecd-nea.org) |
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Member(s): | All NEA member countries* | ||
Russia (Suspended*) | |||
*Russian Federation suspended pursuant to a decision of the OECD Council. | |||
Full participant(s): |
European Commission Under the NEA Statute | ||
Observer(s)(International Organisation): |
International Atomic Energy Agency (IAEA) By agreement | ||
Date of creation: | 30 June 2015 | ||
End of mandate: | 31 March 2024 |
Mandate (Document reference):
Mandate (Document extract):
Extract from document [NEA/SEN/NSC/WPFC(2021)2]
Background
The former Expert Group on Heavy Liquid Metal (HLM) technology was active for several years. Its main objective was to issue a handbook with a collection of theoretical approaches and experimental data in order to deliver recommendations relevant for the design of HLM nuclear systems. Since the second version of the handbook has been published, the expert group has re-discussed its scope and future related activities. In particular, as suggested by the Working Party on Scientific Issues of Advanced Fuel Cycle (WPFC), it has been decided to include liquid sodium (Na) activities in the future work plan of the expert group. Secondly, the expert group will aim to take the next step in the assessment of available data to bring it closer to application in design, construction and licensing issues on the one hand, and operation, in-service inspection, handling and maintenance on the other hand. To better reflect the scope, the name of the expert group is changed to “Expert Group on Reactor Coolants and Components Technology” (EGCoCoT), where the latter term indicates that not only the properties of the coolants themselves are covered but also the effects that a particular coolant has on reactor parts such as, but not limited to, structural materials, chemistry control, thermal hydraulics, component behaviour, safety issues etc.
Scope
Under the guidance of the WPFC, the EGCoCoT will undertake activities with the goal to collect, evaluate and preserve relevant scientific data and to "translate" fundamental scientific understanding into application in support of (1) the Development of construction codes used for design (design rules), (2) Key technical issues for licensing, (3) Recommendations for Operation, Inspection and Handling.
Objectives
The topical areas and objectives of the expert group are:
Environmental conditions and factors that affect materials behaviour relevant for the structural integrity of confinement barriers and components. These include the impact on mechanical properties from the environment such as irradiation effects and liquid metal embrittlement as well as environmental assisted property effects like corrosion.
The objective for this topical area is to assess the environmental effects relevant for construction standards via a fundamental understanding of materials behaviour (corrosion and mechanical properties in the liquid metals and under irradiation). The possibility of experimental data sharing among participants and analyses is to be investigated.
Coolant and cover gas issues. The focus is placed on issues relevant for radiological impact assessment, operation, including maintenance, inspection and handling, etc. Topics to be addressed are the chemistry, radiochemistry and physics of the coolant, its interaction with the cover gas, the impact of irradiation, the influence of corrosion, transport of radionuclides in the coolant, etc.
The objective for this topical area is to answer key technical issues to address radiological impact, operation, handling, maintenance and inspection as relevant for licensing.
Thermal-hydraulics for liquid metals. Thermal-hydraulic behaviour of the coolant is a crucial factor in the sense that it essentially determines a large part of the environmental conditions for materials and the cooling such as the flow distribution and mixing, temperatures distribution, stratification and instabilities, pressure variations, coolant structure interactions, etc.
The objective for this topical area is to collect and assess experimental data in order to improve knowledge of the environmental conditions for materials and the coolant behaviour.
Working Methods
Two taskforces will be established from members of the EGCoCoT which will work in parallel on heavy liquid metal and sodium reactor systems to discuss and compare results in order to identify potential commonalities and synergies.
The activities of the two taskforces are to:
Deliverables
The deliverable of the EGCoCoT will be the following:
Interactions
The expert group will liaise closely with other NEA bodies, in particular those under the NSC and those operating under the guidance of the Committee on the Safety of Nuclear Installations (CSNI) in order to ensure the respective work programmes are complementary and to provide advice and support where required and undertake common work where appropriate. The EGCoCoT will also work in co-operation with the IAEA Nuclear Power Technology Development Section and in particular the Technical Working Group on Fast Reactors (TWG-FR). Key sources of experimental data to be reviewed include (but are not limited to) output from IAEA Coordinated Research Project on Sodium properties and safe operation of experimental facilities in support of the development and deployment of Sodium Cooled Fast Reactors (NAPRO) and the Material Database of the European Commission (MatDB).