Validation of numerical particle tracking inside a HLM reactor with measurements in a water model

Different particles can be formed or accidentally be transported inside the coolant circuit of a Heavy Liquid Metal (HLM) reactor. Being able to track their trajectories and determine their final positions is important for the safety analysis when developing innovative new reactors. In the case of the MYRRHA reactor, which is a reactor cooled with Lead-Bismuth Eutectic (LBE), solid oxides might be produced if impurities react with dissolved oxygen. These solid particles will then be transported within LBE. Also, lead oxide particles can be formed in an accidental scenario in case, for example, of a loss of oxygen control. Computational Fluid Dynamics (CFD) codes are nowadays used to predict the thermal-hydraulics of pool-type reactor. Results obtained by different teams using CFD codes have already been presented. Using the simulated flow field, it is possible with Lagrangian particle tracking to study the behavior of different particles inside LBE. However, to get more confidence in the numerical results, a validation of the numerical approach needs to be performed. For the R&D activities related to the development of MYRRHA, a water model at scale 1/5 has been constructed at the von Karman Institute. This water model is used to validate CFD codes for the thermal-hydraulic behavior and is also used for validation of particle tracking. The paper presents the methodology developed for the validation, the preliminary CFD simulations and the first experimental results of particle tracking. In the methodology, similarity laws used to determine the particle characteristics for the water model are described.