Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Towards a Consolidated Approach for the Assessment of Evaluation Models of Nuclear Power Reactors

Journal Article · · Nuclear Technology
DOI:https://doi.org/10.13182/NT16-47· OSTI ID:1357749
The STARS project at the Paul Scherrer Institut (PSI) has adopted the TRACE thermal-hydraulic (T-H) code for best-estimate system transient simulations of the Swiss Light Water Reactors (LWRs). For analyses involving interactions between system and core, a coupling of TRACE with the SIMULATE-3K (S3K) LWR core simulator has also been developed. In this configuration, the TRACE code and associated nuclear power reactor simulation models play a central role to achieve a comprehensive safety analysis capability. Thus, efforts have now been undertaken to consolidate the validation strategy by implementing a more rigorous and structured assessment approach for TRACE applications involving either only system T-H evaluations or requiring interfaces to e.g. detailed core or fuel behavior models. The first part of this paper presents the preliminary concepts of this validation strategy. The principle is to systematically track the evolution of a given set of predicted physical Quantities of Interest (QoIs) over a multidimensional parametric space where each of the dimensions represent the evolution of specific analysis aspects, including e.g. code version, transient specific simulation methodology and model "nodalisation". If properly set up, such environment should provide code developers and code users with persistent (less affected by user effect) and quantified information (sensitivity of QoIs) on the applicability of a simulation scheme (codes, input models, methodology) for steady state and transient analysis of full LWR systems. Through this, for each given transient/accident, critical paths of the validation process can be identified that could then translate into defining reference schemes to be applied for downstream predictive simulations. In order to illustrate this approach, the second part of this paper presents a first application of this validation strategy to an inadvertent blowdown event that occurred in a Swiss BWR/6. The transient was initiated by the spurious actuation of the Automatic Depressurization System (ADS). The validation approach progresses through a number of dimensions here: First, the same BWR system simulation model is assessed for different versions of the TRACE code, up to the most recent one. The second dimension is the "nodalisation" dimension, where changes to the input model are assessed. The third dimension is the "methodology" dimension. In this case imposed power and an updated TRACE core model are investigated. For each step in each validation dimension, a common set of QoIs are investigated. For the steady-state results, these include fuel temperatures distributions. For the transient part of the present study, the evaluated QoIs include the system pressure evolution and water carry-over into the steam line.
Research Organization:
Idaho National Laboratory, Idaho Falls, ID (United States)
Sponsoring Organization:
USDOE Office of Nuclear Energy (NE)
Grant/Contract Number:
AC07-05ID14517
OSTI ID:
1357749
Report Number(s):
INL/JOU--16-38309
Journal Information:
Nuclear Technology, Journal Name: Nuclear Technology Journal Issue: 2 Vol. 196; ISSN 0029-5450
Publisher:
American Nuclear Society (ANS)Copyright Statement
Country of Publication:
United States
Language:
English

Similar Records

Transition to CASMO-5M and SIMULATE-3K for stability analyses of the Swiss BWRs
Conference · Sun Jul 01 00:00:00 EDT 2012 · OSTI ID:22105816

Convergence studies of deterministic methods for LWR explicit reflector methodology
Conference · Mon Jul 01 00:00:00 EDT 2013 · OSTI ID:22212923

Full core LOCA analysis for BWR/6 - Methodology and first results
Conference · Fri Jul 01 00:00:00 EDT 2016 · OSTI ID:22764108