Analysis of the Scaling between Model Experimental Facilities MYRRHABELLE and E-SCAPE and the MYRRHA reactor augmented by CFD

The design of the cooling system of nuclear reactors is supported by thermal-hydraulic scaled experiments and numerical simulations. In this work, we summarize the experiences gained by the measurements conducted in the scaled water setup, myrrhaBelle, and the scaled liquid metal facility, E-SCAPE of the MYRRHA reactor. The myrrhaBelle facility allows detailed measurements of the flow field due to its transparency allowing the validation of the velocity field in the numerical simulation of pool-type systems. On the other hand, the E-SCAPE facility operates with liquid metal, allowing the validation of the thermal field, but lacking the measurement of velocity. The scenario considered represents a reduced-power operating condition, as the reduced-scale experimental facilities cannot reproduce the high power density of the MYRRHA nuclear core. While the original scaling approach of the experimental facilities was to take the MYRRHA reactor as the reference and try to match the relevant non-dimensional numbers as best as possible, here we have chosen a different road: we take the E-SCAPE facility as a reference and try to match the non-dimensional numbers of a given experiment in E-SCAPE by an experiment in the water facility and then reproduce the flow and thermal field by CFD of all three facilities. Finally, the simulation of the E-SCAPE conditions and the actual operating condition of the MYRRHA reactor will be compared to evaluate the effect of scaling choices for the experimental setups.