Summary of planning lecture at 2017 Annual Meeting

Mon. March 27, 2017 1:00 PM – 2:30 PM

Room G (Tokai University)

”Credibility Assessment of Nuclear Simulations: State of the Art”

Chair person: Seiichi Koshizuka (The University of Tokyo)

Importance and necessity of verification and validation (V&V) is widely recognized in the simulation technology, and activities to establish the guidelines or standards for the simulation credibility are successfully performed in Japan and overseas. In the Atomic Energy Society of Japan, “Guideline for Credibility Assessment of Nuclear Simulations: 2015 (AESJ Guideline)” was published in July 2016. This AESJ Guideline presents the fundamental methodology of the V&V for modeling and simulation and the estimation of predictive capability incorporating with uncertainty quantification under high performance quality management system. In this session, publication process, expectations and issues on the guideline were presented.

（1）Publication of the AESJ Guideline for Simulation Credibility Assessment (in Japanese)

Kotaro Nakada (Toshiba)

The outline of the AESJ Guideline published on July 15, 2016 was presented. This guideline provides a framework to assess credibility of simulations and general concepts to perform the model V&V. It, therefore, describes a procedure of V&V for Modeling and Simulation and requires 4 elements for V&V: development of conceptual model, mathematical modeling, physical modeling and assessing predictability of simulation mode. A procedure to evaluate the uncertainties for prediction after V&V process is also described. Moreover, the outline of seminars on the guideline for spreading the fundamental concepts of assessment activities to acquire credibility of simulations was briefly reported in the presentation.

（2）Expectations for the AESJ Guideline for Simulation Credibility Assessment (in Japanese)

Masaki Shiratori (Yokohama National Univ.)

The Japan Society for Computational Engineering and Science (JSCES), in which speaker’ great effort has led the significant activities to enhance the quality assurance in computational engineering, published “Quality Management of Engineering Simulation”, “A Model Procedure for Engineering Simulation”, and supplemental document with the best practices in application of JSCES Standards. As expectations on the AESJ Guideline in viewpoint of simulation credibility assessment, it was emphasized that the predictive capability of the simulation for a specific purpose which applied to an internal or external events with low probability and high consequence in nuclear related facilities must be shown with high accountability, traceability, transparency and objectively. Additionally, the importance of implementation of the CFD grade experiments to support assurance of predictive capability of simulation was indicated.

（3）Issues and Challenges for Simulation Credibility Assessment (in Japanese)

Masaaki Tanaka (Japan Atomic Energy Agency)

In addition to the AESJ Guideline, “Standard Method for Safety Evaluation using Best Estimate Code Based on Uncertainty and Scaling Analyses with Statistical Approach: 2008” was published from the AESJ to ensure credibility of simulation in nuclear engineering. In foreign societies and organizations such as the American Nuclear Society, American Society of Mechanical Engineers (ASME), OECD/NEA, IAEA, the publication of guidelines regarding the V&V methodology was successfully progressed. In Japan, also, several activities regarding the V&V methodology and related studies have been carried out in, for instance, Japan Aerospace Exploration Academy (JAXA) and Applied Mechanics Committee of Japan Society Civil Engineering.