THE McSAFE PROJECT - HIGH-PERFORMANCE MONTE CARLO BASED METHODS FOR SAFETY DEMONSTRATION: FROM PROOF OF CONCEPT TO INDUSTRY APPLICATIONS

Abstract

The increasing use of Monte Carlo methods for core analysis is fostered by the huge and cheap computer power available nowadays e.g. in large HPC. Apart from the classical criticality calculations, the application of Monte Carlo methods for depletion analysis and cross section generation for diffusion and transport core simulators is also expanding. In addition, the development of multi-physics codes by coupling Monte Carlo solvers with thermal hydraulic codes (CFD, subchannel and system thermal hydraulics) to perform full core static core analysis at fuel assembly or pin level has progressed in the last decades. Finally, the extensions of the Monte Carlo codes to describe the behavior of prompt and delay neutrons, control rod movements, etc. has been started some years ago. Recent coupling of dynamic versions of Monte Carlo codes with subchannel codes make possible the analysis of transient e.g. rod ejection accidents and it paves the way for the simulation of any kind of design basis accidents as an alternative option to the use of diffusion and transport based deterministic solvers. The H2020 McSAFE Project is focused on the improvement of methods for depletion considering thermal hydraulic feedbacks, extension of the coupled neutronic/thermal hydraulic codes by the incorporation of a fuel performance solver, the development of dynamic Monte Carlo codes and the development of methods to handle large depletion problems and to reduce the statistical uncertainty. The validation of the multi-physics tools developed within McSAFE will be performed using plant data and unique tests e.g. the SPERT III E REA test. This paper will describe the main developments, solution approaches, and selected results.

Multiphysics modeling of a reactivity insertion transient at different fidelity levels in support to the safety assessment of a SMART-like small modular reactor

“…This trend is also driven by large and cheap HPC-clusters for massive parallel computing. In this context and within the framework of the EU H2020 McSAFE Project (Sanchez-Espinoza, et al, 2021), several attempts have been undertaken to develop Monte Carlo-based high-fidelity coupling schemes capable to simulate pin-by-pin full cores' behaviour both at steady state but also with burnup and time dependent capabilities. In particular, a new beyond state-of-the-art master-slave coupled code was developed based on Serpent2 (as master) and SCF (as slave) (Ferraro et al, 2020a;Ferraro et al, 2020b;Ferraro et al, 2020c).…”

“…The use of these advanced simulation methodologies at high resolution is possible nowadays due to availability of HPC architectures at a relatively low cost. As a part of this trend, novel high-fidelity methods have been recently developed that couple continuous energy Monte Carlo neutronics tools with sub-channel thermal hydraulics solvers (Sanchez-Espinoza, et al, 2021). These beyond the state-of-theart solvers have the drawback of the significant runtime, but due to their fewer approximations on the core physics when compared with the low-order tools, they are used to provide reference solutions for those cases where little or no experimental data are available.…”