Edge-wise perturbations to model vibrating fuel assemblies in the frequency-domain using FEMFFUSION: Development and verification

•This work presents the implementation of a frequency-domain finite element method in the FEMFFUSION code to simulate mechanical vibrations in hexagonal reactors.•The perturbations are introduced on the edges of the cells without the necessity of using locally refined meshes.•The proposed edge-wise method is tested against the usual cell-wise model in the frequency-domain (CORE SIM+) and time-domain methodologies (FEMFFUSION-TD and PARCS).•The proposed code have been verified against a one-dimensional homogeneous reactor, simplified two-dimensional rectangular and hexagonal reactors and a VVER-1000 reactor.