Mathematical Modeling and Computational Analysis of the Neutron-Physical Parameters of the IR-8 Reactor with Conversion to Low-Enrichment Uranium Fuel

Abstract

A comparative computational analysis of the neutron-physical parameters is made for the IR-8 reactor using core fuel assemblies containing fuel based on low-enrichment uranium: IRT-3M (in development), IRT-4M (in use), and IRT-4M-290 (proposed) with increased (to 290 g) 235U content in six-tube fuel assemblies. The neutron-physical parameters for equilibrium loads of a reactor with conversion to different types of low-enrichment uranium fuel are obtained by means of a computational analysis using the MCU-PTR Monte-Carlo code verified for IR-8. The neutron flux density, estimated fuel costs, and neutron irradiation when using these fuel assemblies are presented relative to the IRT-3M operating fuel assemblies with high-enrichment uranium are presented. It is shown that a load 290 g load (increased from 264 g) in the six-tube IRT-4M fuel assemblies is expedient.