Since 2013, the Laboratory for Reactor Physics and Thermal-Hydraulics at the PSI and the Laboratory for Reactor Physics and Systems Behaviour at the EPFL are working towards the development of a multi-physics platform for coupled reactor analysis based on the CFD-oriented library OpenFOAM^®. The developed tool, named GeN-Foam, includes steady state and transient solvers for multi-group neutron diffusion, SP3 and discrete ordinates, and it provide us with the possibility to use unstructured meshes, which can be of interest to improve the modeling of the unconventional geometries often found in research reactors. Form functions are employed as a pin-by-pin power reconstruction method. This paper presents the current GeN-Foam model of the zero power reactor CROCUS at the École Polytechnique Fédérale de Lausanne and reports its validation against measurements performed at the facility. Axial and radial fission rate profiles measurements are
compared to computational results produced with the SP3 solver of GeN-Foam. The paper also discusses the ongoing efforts towards improvements of the model, and in particular for the separate modeling of the two fuel lattices that are present in CROCUS thanks to an unstructured mesh.