J. Blair Briggs

The International Criticality Safety Benchmark Evaluation Project

Abstract The International Criticality Safety Benchmark Evaluation Project (ICSBEP) was initiated in 1992 by the U.S. Department of Energy. The ICSBEP became an official activity of the Organisation for Economic Co-operation and Development (OECD) Nuclear Energy Agency in 1995. Representatives from the United States, United Kingdom, France, Japan, the Russian Federation, Hungary, Republic of Korea, Slovenia, Yugoslavia, Kazakhstan, Spain, and Israel are now participating. The purpose of the ICSBEP is to identify, evaluate, verify, and formally document a comprehensive and internationally peer-reviewed set of criticality safety benchmark data. The work of the ICSBEP is published as an OECD handbook entitled “International Handbook of Evaluated Criticality Safety Benchmark Experiments” (ICSBEP Handbook). The 2002 edition of the ICSBEP Handbook contains benchmark model specifications for 2881 critical or subcritical configurations that are intended for validating computer codes that calculate effective neutron multiplication and for testing basic nuclear data.

DICE: Database for the International Criticality Safety Benchmark Evaluation Program Handbook

Abstract The 2002 edition of the “International Handbook of Evaluated Criticality Safety Benchmark Experiments” (ICSBEP Handbook) spans more than 26 000 pages and contains 330 evaluations with benchmark specifications for 2881 critical or near-critical configurations. With such a large content, it became evident that the users needed more than a broad and qualitative classification of experiments to make efficient use of the ICSBEP Handbook. This paper describes the features of Database for the International Handbook of Evaluated Criticality Safety Benchmark Experiments (DICE), which is a database for the ICSBEP Handbook. The DICE program contains a relational database loaded with selected information from each configuration and a users’ interface that enables one to query the database and to extract specific parameters. Summary descriptions of each experimental configuration can also be obtained. In addition, plotting capabilities provide the means of comparing neutron spectra and sensitivity coefficients for a set of configurations.

Applications of Integral Benchmark Data

Abstract The International Reactor Physics Experiment Evaluation Project (IRPhEP) and the International Criticality Safety Benchmark Evaluation Project (ICSBEP) provide evaluated integral benchmark data that may be used for validation of reactor physics/nuclear criticality safety analytical methods and data, nuclear data testing, advanced modeling and simulation, and safety analysis licensing activities. The handbooks produced by these programs are used in over 30 countries. Five example applications are presented in this paper: (a) use of IRPhEP data in uncertainty analyses and cross-section adjustment, (b) uncertainty evaluation methods for reactor core design at Japan Atomic Energy Agency using reactor physics experimental data, (c) application of benchmarking data to a broad range of criticality safety problems, (d) cross-section data testing with ICSBEP benchmarks, and (e) use of the International Handbook of Evaluated Reactor Physics Benchmark Experiments to support the power industry.

An Overview of the International Reactor Physics Experiment Evaluation Project

Abstract Interest in high-quality integral benchmark data is increasing as efforts to quantify and reduce calculational uncertainties associated with advanced modeling and simulation accelerate to meet the demands of next-generation reactor and advanced fuel cycle concepts. Two Organisation for Economic Co-operation and Development (OECD)/Nuclear Energy Agency (NEA) activities, the International Criticality Safety Benchmark Evaluation Project (ICSBEP), initiated in 1992, and the International Reactor Physics Experiment Evaluation Project (IRPhEP), initiated in 2003, have been identifying existing integral experiment data, evaluating those data, and providing integral benchmark specifications for methods and data validation for nearly two decades. Data provided by those two projects will be of use to the international reactor physics, criticality safety, and nuclear data communities for future decades. An overview of the IRPhEP and a brief update of the ICSBEP are provided in this paper.

Polyethylene-Reflected Arrays of HEU(93.2) Metal Units Separated by Vermiculite

This benchmark details the results of an experiment performed in the early 1970s as part of a series testing critical configurations in three dimensional arrays. For this experiment, cylinders of 93.2% enriched uranium metal were arranged in a 2x2x2 array inside of a polyethylene reflector. Layers of vermiculite of varying heights were surrounding each cylinder to achieve criticality variations. A total of four experimental configurations were tested by D.W. Magnuson, and detailed in his experimental report “Critical Three-Dimensional Arrays of Neutron Interacting Units: Part IV. Arrays of U(93.2) Metal Reflected by Concrete and Arrays Separated by Vermiculite and Reflected by Polyethylene.” The benchmark HEU-MET-FAST054 is closely related; the results of both experiments are discussed in the same report (Ref. 1) Closely related work has been recorded in HEU-MET-FAST-053, which is a benchmark evaluation of a different series of three dimensional array experiments with four different moderator materials. HEU-MET-FAST-023 and HEU-MET-FAST-026 are also related because they utilize the same metal cylinders as these experiments.