Technical Meeting on Safety and Performance Aspects in the Development and Qualification of High Burnup Nuclear Fuels for Water-Cooled Reactors

Introduction

Increased rates of fuel discharge burnup (e.g., beyond 62 GWd/tU) are being pursued by Member States, including in the framework of the development of advanced technology for nuclear fuel (which include so-called Accident Tolerant Fuels or Advanced Technology Fuels), particularly in association with advanced fuel and cladding materials, which might require higher fissile enrichment rates (in some cases exceeding 5%) in order to counterbalance increased parasitic neutron absorption in the cladding. Some nuclear fuel vendors and NPP operators are even exploring the possibility of increasing the operating envelope up to 80 GWd/tU, which would imply the need to address considerable technical challenges, such as:

• Improvement of nuclear fuel analytical codes for the accurate prediction of fuel behaviour and performance at higher burnups;
• Update of source term calculations;
• Modifications for higher heat loads in the spent fuel pool;
• Performance of design and safety analyses at higher burnups addressing potentially new phenomena, including Fuel Fragmentation Relocation and Dispersal (FFRD);
• Possible degradation of safety performance in normal operation and in accident conditions, posing considerable challenges for the development and qualification of high burnup nuclear fuels.

Objectives

The objective of the event is to provide a platform for Member States to exchange information on safety and performance of high burnup nuclear fuels for WCR, considering their development, qualification and licensing.
The event will focus on operational experience of, and margins assessment by, licensee organizations, experience of fuel developers in the development and qualification of fuel designs and irradiation of ‘lead test’ or ‘lead use’ fuel rods beyond 62 GWd/tU, experimental testing in research reactors and associated modelling and simulation, validation and application of computer codes and methods for fuel design and safety analysis, and practices by national regulators and technical support organizations in development or adaptation of licensing frameworks for high burnup nuclear fuels.

Target Audience

The event is targeted at professionals from nuclear fuel or reactor design organizations, licensee organizations, national regulators, technical support organizations and research organizations with specialized knowledge of, or experience in, nuclear fuel development, qualification and licensing, or any other activity related to high burnup nuclear fuel safety and performance.

Topics

The scope of this Technical Meeting will encompass design, qualification, licensing, and in-reactor operation of UO2-Zr-based alloys (including doped-UO2 and coated cladding), with discharge burnup exceeding 62 GWd/tU (fuel rod average) or 55 GWd/tU (fuel assembly average), or other equivalent criteria.
The event is intended to cover the following topics:

• Licensee organisations’ operational experience and margins assessment at high burnup;
• Experience of fuel developers in development and qualification of fuel designs for high burnup, including advanced fuel and cladding designs, irradiation of test fuel rods beyond 62 GWd/tU, pool-site inspections and post-irradiation examinations;
• Experimental testing (in-pile and out-of-pile) and associated multiphysics and multiscale modelling and simulation of fuels at high burnup;
• Adequacy of safety design criteria at high burnup;
• Validation and application of computer codes and methods for design and safety analysis for high burnup fuels;
• Practices by national regulators and technical support organizations in development or adaptation of licensing frameworks for nuclear fuels to address specific safety features of high burnup nuclear fuels, with focus on regulatory expectations from qualification process, and opportunities for harmonization of national licensing approaches;
• Industry experience in performing economic assessments of expected benefits of increased burnup rates.

Key Deadlines and Dates

14 September 2022: Deadline for submission of the Participation Form (Form A) and if applicable the Form for Submission of a Paper (Form B) and the Grant Application Form (Form C) to the competent national authority (e.g., Ministry of Foreign Affairs, Permanent Mission to the IAEA or National Atomic Energy Authority) or their organization for onward transmission to the IAEA.

14 September 2022: Deadline for submission of abstracts to the Scientific Secretary.

4 October 2022: Notification of acceptance of abstracts for oral presentations.

14-18 November 2022: Meeting dates.