Benchmarking of CFD modelling of a reactor vessel auxiliary cooling system (RVACS)

Abstract

This dataset provides benchmark computational-fluid-dynamics (CFD) results for forced, mixed and natural convection flows in a simplified Reactor Vessel Auxiliary Cooling System (RVACS), generated for the Collaborative Computational Project in Nuclear Thermal Hydraulics (CCP-NTH). The geometry represents the RVACS as planar inlet and outlet channels separated by a baffle plate and connected at the bottom, with heated inner and cooled outer walls. Three-dimensional direct numerical simulations (DNS) were performed with the low-Mach-number spectral-element solver Nek5000 on ARCHER2 and provide the high-fidelity reference solution. 2/3-D Reynolds-averaged Navier-Stokes (RANS) simulations were contributed by participating organisations using engineering CFD approaches, including Code\_Saturne, FEAT and Ansys Fluent, with a range of turbulence models, wall treatments, mesh resolutions and steady or unsteady solution strategies. The dataset contains post-processed results from both DNS and RANS calculations for the forced convection, mixed convection and natural convection cases. It includes mean vertical velocity, mean temperature and turbulent kinetic energy profiles extracted along twelve uniformly spaced horizontal probe lines through the RVACS domain. It also includes wall shear stress and wall heat flux distributions along the hot wall, cold wall and baffle surfaces. DNS fields were averaged in time and in the transverse direction before extraction, while RANS results were extracted directly from the two-dimensional solutions; unsteady RANS data were time averaged after reaching statistically stationary behaviour. These data support comparison of turbulence modelling strategies for buoyancy-affected separated flows and passive reactor cooling applications.