The Liquid Metal Fast Reactor (LFMR) is one of the next generation reactor designs, and many numerical and experimental studies have been performed on LMFR core geometry. To establish best practise guidance for LMFR thermal hydraulics simulations and to compare different numerical appraoches on an international level, a benchmark was prepared jointly by North Carolina State University (NCSU) and Texas A&M University (TAMU), USA, in co-operation with the United States Nuclear Regulatory Commission (US NRC) and OECD Nuclear Energy Agency (NEA). The work is supported by the US NRC (Grant 31310021M0009) and endorsed by the NEA. The benchmark is part of the Expert Group on Reactor Core Thermal-Hydraulics and Mechanics (EGTHM) activities.
The LMFR T/H benchmark consists of two Phases:
Each phase will include several exercises and will be planned to accommodate as many numerical prediction methods as possible.
The objectives of Phase I are to provide a detailed geometry of the bundle test section and boundary conditions and a high-resolution experimental database of isothermal turbulent flow and pressure drop acquired from a 61-pin wire-wrapped hexagonal fuel bundle (all from TAMU); assess the performance of numerical schemes and turbulent models currently implemented in the state-of-the-art Computational Fluid Dynamics (CFD) codes; and establish best practices for uncertainty quantification (UQ) of model geometry, initial and boundary conditions, and other associated uncertainties for CFD calculations.
The objectives of Phase II are to provide a sodium turbulent flow and heat transfer database for CFD and subchannel model validation; emphasize the importance of uncertainty analysis for TH simulations; establish best practices for quantification of geometry modelling, input data, fluid properties, and other uncertainties associated with the complex flows in LMFR bundles; develop guidance for CFD model/code validation for LMFR fuel bundles that can be used to improve the existing standards; update the current TH models for pressure drop and inter-channel mixing; and develop the hybrid experiment/simulation database necessary to establish and calibrate the low order models with high resolution (both experimental/numerical) data.
Benchmark coordinator: Maria N. Avramova (USA) and Yassin A. Hassan (USA)
Participants: All NEA member countries LMFR T/H Participants' working area
Access to the benchmark is open to all OECD/NEA member countries and it requires only acceptance of the benchmark conditions.