Nuclear Fuel Cycle and Materials Section

Technical Working Group on
Water Reactor Fuel Performance and Technology (TWGFPT)


SUMMARY REPORT OF THE 2002 TWGFPT INTERMEDIATE MEETING

The Technical Working Group on Fuel Performance and Technology held its 2002 Intermediate meeting in Vienna from May 13-15, 2002.

In his welcome speech, Mr Bonne, Director of the Division of Nuclear Fuel Cycle and Waste Technology, noted that the topic of Water Reactor Fuel Performance and Technology had been elevated from the Project level to the Sub-Programme level for the current and the next cycles of programmes and budgets. This should provide greater visibility of this Working Group’s activities. He also noted the establishment of a new International Project on Innovative Nuclear Reactors and Fuel Cycles (INPRO) which it is hoped will ultimately identify innovative technologies that might be appropriate for implementation by Member States within the framework of an international project.

Mr Dyck, Acting Head of Nuclear Fuel Cycle and Materials Section, presented the current status of Agency programme B on Nuclear Fuel Cycle and Material Technologies (2002-03 and proposals for 2004-05) in the framework of Major Programme 1 “Nuclear Power, Fuel Cycle and Nuclear Science”. The WG expressed its continued support for the direction of this programme.

Mr Onoufriev, Scientific Secretary, noted the recent activities of the Standing Advisory Group on Nuclear Energy (SAGNE). The WG supported the efforts of SAGNE and the Secretariat to clarify the hierarchy of the advisory group structure and to harmonise the terms of reference of the various WGs.

The principal findings and conclusions from various CRPs and TMs were presented by Mr Onoufriev, Mr Sokolov, Mr Ronnberg and Mr Ritchie. The topics covered were :

  • CRP on Hydrogen And Hydride Degradation Of The Mechanical And Physical Properties Of Zr-Based Alloys

  • CRP on Data Processing Technologies And Diagnostics Of Water Chemistry And Corrosion Control In NPP’s (DAWAC)

  • CRP on Improvement Of Models Used For Fuel Behaviour Simulation (FUMEX II)

  • TM on Advancements In PIE Techniques For Water Reactor Fuel (Dimitrovgrad)

  • TM on Fuel Behaviour Under Transient And LOCA Conditions (Halden)

Mr Ritchie noted, in particular, the highly successful organisation of the Hydrogen and Hydride Degradation CRP based around a host laboratory providing consistent samples supported by guidance from a small Supervisory Group of experts.

The WG greatly appreciated the presentation by Ms Feltus on the USDoE’s Nuclear Energy Research Initiative (NERI). It was noted that many NERI projects involve the research and development of novel fuel designs that enhance proliferation resistance, reduce waste, improve corrosion performance and address high burnup and increased initial fuel enrichment issues. The WG welcomed the positive steps which the US is taking in these areas and looked forward to receiving future updates to these initiatives.

Mr Niehaus, Head of the Safety Assessment Section (SAS/NSNI/NS), presented the latest findings of the project on the Analysis of Differences in Fuel Safety Criteria between PWRs and VVERs, following a recent TCM on VVER Local Power Peaking Induced by Control Rods. It is hoped that a finalised TECDOC on this topic will be available before the end of the year.

Mr Sartori gave a presentation on the OECD/NEA-IAEA IFPE fuel performance database. The WG noted the need for continued maintenance of this database for which the feedback from users was important. During the execution of the FUMEX-II CRP, for example, many questions will be raised and errors may be found. In order to support the IFPE database in their maintenance work, the WG recommended that some funds should be allocated for correction of errors and revision of specific datasets.

The tentative programme for the TCM to be held in Slovakia on Fuel Failure Causes and Their Mitigation was presented by Mr Petenyi, and the WG expressed its support.

The plans for a TCM on Improved Fuel Pellet Materials and Designs were updated. The focus will be on high burnup data for fuel with additives and modified microstructures, and the meeting will be hosted by Belgium in late October 2003.

The plans for a TCM in France in 2004 on Fuel Assembly Structural Behaviour at High Burnup were confirmed. The scope should include assembly bow, Incomplete Rod Insertion, water gap issues and vibrations including loop testing. Experiences, as well as analyses and modelling, should be included. The WG expressed the opinion that these are important topics both for PWRs and for WWERs.

The plans for a TCM hosted by Korea in 2004 on the Behaviour of Highly Corrosion Resistant Zirconium-based Alloys were updated. The scope should include corrosion, mechanical properties and creep and growth. The possible overlap with the next ASTM Zirconium conference was discussed. As that conference is in Sweden, the conclusion was that the interference would be limited, but a time gap of at least a few months was recommended.

The plans for a TCM on Advanced Water Reactor Fuels (to burn MAs and IMF) were updated. The group noted that there is a series of workshops covering this topic, and that cooperation with that group should be sought. The Scientific Secretary agreed to contact the Chairman of that group with a view to organizing one of these future meetings as a TCM hosted by Russia.

The plans for a TCM on Poolside Inspection and Repair of Water Reactor Fuel were updated. The Agency has no funding for this in 2003. The WG noted that the greatest interest in this topic is in Brazil and Argentina and expressed its support for a TCM hosted by one of these countries in 2005. The scope should also include NDE techniques and experiences. Brazil expressed a specific interest in criteria for reconstitution of fuel with wear damage.

The plans for a new TCM on Fuel Behaviour Modelling to be held in 2005 were confirmed. This continues a series of meetings in this important area and will again be hosted by the UK.

A possible new TCM on thorium-based fuels was suggested. The focus should be on materials properties, fabrication and experiences, and interest was expressed by India, Canada and the US. This will be discussed again in more detail at our next meeting and might be arranged in 2006.

A possible TCM on the use of advanced technologies, for example IT, in fuel fabrication and performance analyses was mentioned. This will be brought up again for more detailed consideration at our next meeting.

A possible TCM on accelerator techniques for simulation of irradiation damage in fuel materials was suggested, possibly for hosting by the US. This will be brought up for discussion at the next meeting.

Meetings in cooperation were also discussed.

There were different opinions about the plans for future ANS Fuel Topical Meetings and ENS TOPFUEL meetings and ASTM Zr conferences. The plans will be clarified and taken into consideration by the Scientific Secretary in the detailed planning of IAEA TCMs.

It was noted that the two special meetings to be arranged in France, on PCI at high burnup and on Microbeam (SIMS) techniques, have been deferred to 2003.

It was also noted that the meeting in India on Characterisation and QA/QC in Nuclear Fuel Fabrication will take place in December this year and that invitations have already been distributed. The WG expressed its support.

The plans for the next Seminar on WWER Fuel Modelling to be held in Bulgaria in 2003 were confirmed.

During discussion of ongoing and planned CRPs, the WG noted that these are much appreciated by the participants as well as by the host organisations.

The ongoing CRP on Hydrogen Content Measurement and DHC Measurements will be finished next year, and a follow-up CRP on crack propagation studies using the Studsvik PLT technique is in an advanced planning stage with more than 20 interested laboratories, and the WG expressed its strong support.

The FUMEX-II plans were discussed in some detail. The plans do incorporate the WG’s previous recommendations not to plan for a blind exercise and to include high burnup data and WWER data. The data to be used should also be introduced into the OECD/NEA-IAEA IFPE database. It was recommended that an extra day of the first FUMEX-II RCM be devoted to reviewing the IFPE database and that experts from outside FUMEX-II should be invited to participate in this exercise. The WG also noted the lack of fuel vendor participation in the present plans and suggested that the Agency make direct contacts with these organisations about possible participation.

During discussions about Expert Reviews, it was noted that the review of Mechanical Properties of Zr- based Alloys is delayed. The WG expressed its continued interest in this activity as well as in the plans for an updated review on fuel failure mechanisms. The TWGFPT recognised that updating the fuel failure review in 2004 is desirable in order to present the evolution over the previous 7 years. This expert review should be based on specific data collected from conferences and meetings, such as the next TCM in Slovakia, and on data incorporated in the country reports at the regular plenary meetings of the TWGFPT. The Scientific Secretary is invited to draw the attention of participants to include relevant data on this topic in their country reports.

Tentative plans for a Symposium devoted to fuel fabrication and out-of-core fuel activities were discussed. The Agency’s position will be clarified before the next WG meeting, when this issue will be discussed again.

The TWG and the Agency staff noted that the previous Chairman, Mr Stratton, had left the group and, through Mr Ott, sent its very best regards and thanks to Mr Stratton for his invaluable contributions to the IWGFPT.

The next TWGFPT meeting is planned to take place in Vienna from 12th to 14th of May 2003 and will be a regular plenary meeting with country reports.