Investigation of the Self-Interrogation Neutron Resonance Densitometry applied to spent fuel using Monte Carlo simulations

•Assessment of the performance of the SINRD technique.•Study of the neutron flux in the central guide tube of a fuel assembly.•Neutron flux reduction due to the 239Pu resonance more evident in dry conditions.•Ratio between fast flux and flux around the 0.3eV resonance as signature.•SINRD is more sensitive to 239Pu and 235U, less sensitive to 240Pu, 241Pu and 241Am.