OECD/NRC MSLB Benchmark - A Systematic Approach to Validate Best- Estimate Coupled Codes Using a Multi-Level Methodology

The paper describes the basis of a consistent and comprehensive methodology to validate coupled system thermal-hydraulics (T-H)/three-dimensional (3D) neutronics codes, implemented in the specifications of the OECD/NRC MSLB benchmark. In order to meet the objectives of the validation of best-estimate coupled codes a systematic approach has been introduced to evaluate the MSLB transient. Multi-level methodology is employed including the application of three exercises (phases), evaluation of several steady states, and simulation of two transient scenarios. Since the MSLB benchmark is based on code to code comparisons further guidance for presenting and evaluation of results has been established employing a statistical methodology. (authors)