A design of a universal gamma-ray emission tomography (UGET) device has been definedwithin the IAEA MSSP project JNT1955 in order to evaluate partial defect detectioncapabilities when using tomography on used nuclear fuel assemblies. The design isintended to allow for fuel assembly verification using single photon emission tomographyon a broad range of fuel assembly types and fuel parameters.
In this paper, results from a set of Monte Carlo radiation transport simulations for the UGETdesign are presented. In these simulations, two cases are studied, each of them with a PWR fuel, in one case the complete fuel assembly and in the other with 11 missing rods.The characteristic features of the design are presented including expected performancerequirements on the gamma-ray collimator and detector system, supported by thesimulation results. In addition, the agreement between the two simulation tools used, Geant4 and MCNP, indicate that any of the two can give satisfactory accuracy for this purpose.