NURETH-21: Advancements in Nuclear Reactor Thermal Hydraulics
The 21st International Topical Meeting on Nuclear Reactor Thermal Hydraulics (NURETH-21) took place between August 31 and September 5, 2025, in the vibrant city of Busan, Korea. Organized in collaboration with the OECD Nuclear Energy Agency (NEA), this conference served as a vital platform for experts in the field of nuclear safety and thermal hydraulics.
A Gathering of Global Experts
NURETH-21 welcomed over 900 participants from nearly 40 countries, bringing together a diverse array of institutions. Attendees included representatives from research organizations, regulatory bodies, industry, and academia. This mix provided rich opportunities for networking and shared learning among professionals dedicated to advancing the nuclear sector.
The conference featured a staggering 700 technical papers distributed across 12 technical tracks. These presentations covered a wide range of topics, including advanced thermal-hydraulic experiments, benchmarking of system codes, and the intricate world of computational fluid dynamics (CFD) in nuclear safety studies. Notably, there was a strong emphasis on emerging reactor designs, particularly non-water cooled reactors and small modular reactors (SMRs). This focus signifies a pivotal shift in the industry as it evolves to meet modern energy demands and safety standards.
Key Contributors and Their Insights
The Technical Programme Committee for NURETH-21 was chaired by Ki-Yong Choi from KAERI, who is also the Chair of the NEA Committee on the Safety of Nuclear Installations (CSNI). His leadership ensured that the technical discourse was both rigorous and relevant. The NEA made several contributions, with experts participating in technical presentations, session chairing, and co-ordinating various activities throughout the conference.
The opening keynote was delivered by Véronique Rouyer, Head of the NEA Division of Nuclear Safety Technology and Regulation. Her address highlighted the critical role of thermal hydraulics in ensuring defense-in-depth strategies and managing severe accidents. This foundational aspect lays the groundwork for maintaining safety protocols across nuclear facilities.
Martina Adorni, a Nuclear Safety Specialist at the NEA, was also pivotal at the event. Serving on the International Advisory Committee, she co-led a technical track on special topics and presented findings related to the NEA’s Working Group on Analysis and Management of Accidents (WGAMA). Her discussions revolved around enhancing safety through international cooperation and shared data.
Innovative Frameworks and Collaborative Results
Another significant contribution came from Didier Jacquemain, a Senior Nuclear Safety Specialist at the NEA, who co-led a technical track focused on severe accidents. He introduced the NEA Framework for Advanced Thermalhydraulic Experiments for Nuclear Analysis and Safety Applications (ATHENA), underscoring the initiative’s commitment to fostering innovative research in thermal hydraulics.
In addition to individual presentations, the NEA organized progress meetings on the ATHENA framework, emphasizing the collaboration between member countries and stakeholders. These meetings serve to propel forward-looking initiatives aimed at refining methodologies and enhancing the safety of nuclear installations globally.
The Importance of International Cooperation
The NURETH-21 conference was not merely an academic gathering; it acted as a critical venue for highlighting ongoing international developments related to WGAMA activities and other NEA Nuclear Safety Joint Projects. These initiatives are designed to support the safe operations of nuclear facilities worldwide. By closing knowledge gaps and providing high-quality experimental data, these joint projects play an essential role in ensuring the future of nuclear energy remains both safe and efficient.
As the nuclear industry continues to evolve, the insights shared at NURETH-21 provide an invaluable foundation for future developments. Through collaborations, research endeavors, and technological advancements, the field of nuclear reactor thermal hydraulics is poised for remarkable growth.