International Criticality Benchmark Comparison for Nuclear Data Validation Isabelle Duhamel, 1 J. L. Alwin, 2 F. B. Brown, 2 M. E. Rising, 2 K. Y. Spencer, 2 D. Heinrichs, 3 S. Kim, 3 B. J. Marshall, 4 E. M. Saylor 4 1 IRSN, Fontenay-aux-Roses, France, [email protected]2 Los Alamos National Laboratory, Los Alamos, USA, [email protected], [email protected], [email protected], [email protected]3 Lawrence Livermore National Laboratory, Livermore, USA, [email protected], [email protected]4 Oak Ridge National Laboratory, Knoxville, USA, [email protected], [email protected]https://dx.doi.org/10.13182/T30859 INTRODUCTION Under a collaborative effort between the US Department of Energy (DOE) Nuclear Criticality Safety Program (NCSP) and the French Institut de Radioprotection et de Sûreté Nucléaire (IRSN), IRSN is leading a benchmark intercomparison effort using a large selection of criticality safety benchmarks. This task is carried out by using the IRSN MORET Monte Carlo code [ref. 1] together with various nuclear data libraries, namely JEFF-3.3, ENDF/B-VII.1 and ENDF/B-VIII.0. IRSN collates its results together with those from Lawrence Livermore National Laboratory (LLNL), Los Alamos National Laboratory (LANL) and Oak Ridge National Laboratory (ORNL) using respectively the COG [ref. 2], MCNP [ref. 3] and KENO (SCALE package) [ref. 4] Monte Carlo codes associated with ENDF/B-VII.1 library. LLNL also shared in 2019 their COG results using ENDF/B-VIII.0 and JEFF-3.3. Due to the large number of benchmarks involved (about 3000), this effort is envisioned to take three years and is currently focused on High Enriched Uranium (HEU) and Plutonium systems (PU). About 760 HEU and 500 PU benchmarks taken from the ICSBEP handbook [ref. 5] covering a large energy spectra range (from thermal to fast) and a wide range of isotopes are considered. METHODOLOGY The benchmark development has been performed independently with most of the cases being taken from each codes validation suites. Results were provided with Monte Carlo standard deviation of about 10 pcm for all the codes. Table I gives the number of HEU and PU benchmarks calculated with the different Monte Carlo codes. TABLE I. Calculated benchmarks in validation suites MORET 5 (IRSN) COG (LLNL) MCNP (LANL) KENO (ORNL) HEU systems 447 761 378 102 PU systems 215 526 261 93 Despite the huge number of calculated benchmarks, only 35 configurations for HEU and 33 for PU systems were common to the four codes. Thus, it was decided to focus first on the common benchmarks and also to perform code to code comparison. This paper discusses mainly the results obtained for these 68 common benchmarks, which are briefly described in Table II. TABLE II. Main characteristics of the common benchmarks HST HMF PST PMF Number of experiments 14 21 26 7 Isotopic composition 93% 235 U 235 U> 89% 239 Pu > 95% 239 Pu > 94% Concentration 20 to 360 g/l - 25 to 140 g/l - Moderator Water None, Be, BeO Water None Poison None or boron None None None Reflector None None, Mo, Be, BeO, CH 2 , V, Steel, Depleted uranium Water None, Unat, Th, Be, W, Steel RESULTS Preliminary analysis When analyzing the calculation results using the same nuclear data libraries for these common benchmarks, discovery of discrepant results helped to highlight modeling errors, which were reported to the codes validation teams. Transactions of the American Nuclear Society, Vol. 121, Washington, D.C., November 17–21, 2019 873 Recent Nuclear Criticality Safety Program Technical Accomplishments
4
Embed
Recent Nuclear Criticality Safety Program Technical ...
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
International Criticality Benchmark Comparison for Nuclear Data Validation
Isabelle Duhamel,1 J. L. Alwin,2 F. B. Brown,2 M. E. Rising,2 K. Y. Spencer,2 D. Heinrichs,3S. Kim,3 B. J. Marshall,4 E. M. Saylor