This work takes place within the framework of fluid-structure interactions inside the core of pressurized water reactors. The core is composed of dozens of fuel assemblies, which can be roughly described as bundles of rods held together by, and passing through, a set of grids. Fuel assemblies are key components of the core, that is why power plant operators seek to continuously enhance the understanding of their behaviour. They notably respond to the hydraulic loads exerted by the core’s coolant flow, yielding a major need for the simulation of fluid-structure interaction between coolant flow and fuel assemblies. This interaction technically translates itself into the iterative coupling between a structural solver and a fluid one. However, the flow within the core is itself highly complex and, for example, inaccessible to CFD approaches at full scale. CFD methods are at best capable of reasonably capturing the flow through two or three assemblies. Thus, making these approaches impractical for iterative resolution between a fluid solver and a structural one. Simplified homogenized formulations are thus much more suited to model the full core flow and implement a coupling with the calculation of the quasi-static displacements of fuel assemblies. A promising approach in this regard involves modeling the various flow paths through the core as interconnected pipes and solving the flow as a hydraulic network [1]. The present work aims to adapt and extend this approach, validated on demonstrative examples at this stage, to get closer to the industrial situation of interest. It will first target new experimental setup Eudore located at CEA, hosting 3 half-scale fuel assemblies in a line with unbalanced flow inlet at their bottom [2]. These results shall represent a first step to consolidate the hydraulic network approach prior to fluid-structure interaction calculations on a full-scale core model with all its fuel assemblies. REFERENCES [1] S. Lambert, J. Cardolaccia, V. Faucher, O. Thomine, B. Leturcq, G. Campioni, “Semi-analytical modeling of the flow redistribution upstream from the mixing grids in a context of nuclear fuel assembly bow”, Nuclear Engineering and Design, Vol. 371, 2021 [2] L. Longo, K. Cruz, N. Cadot, E. Sarrouy, G. Ricciardi, C. Eloy, “Drag coefficient estimation in FSI for PWR fuel assembly bowing”, Nuclear Engineering and Design, Vol 399, 2022