Research and Validation of the Monte Carlo-based multi-cycle neutronic Simulations methodology for HFETR

Abstract

The High Flux Engineering Test Reactor (HFETR) is a distinctive reactor that exhibits notable differences in design and operational characteristics compared to commercial pressurized water reactors. The reactor is distinguished by a sophisticated core composition, an adaptable core loading configuration, and pronounced heterogeneity. In order to achieve this, the RMC Monte Carlo transport-burnup coupling code was employed. The developers constructed a sophisticated computational model to simulate global core and localized fuel irradiation. This model effectively captures the physical dynamics of the core across multiple loops, incorporating a range of variables, including fuel burnup, control rod positioning, beryllium poisoning, and particle transport during reactor operations. The methodology comprises comprehensive refueling and fuel management calculations for an array of fuel types and burnable poisons, coupled with the formulation of a multi-cycle neutronic calculation framework. An evaluation of core reactivity and average point burnup for different fuel irradiation cycles reveals a high alignment between the calculated and experimental data, with an average relative error below 1000 pcm and 10%. This outcome provides substantial evidence supporting the accuracy of the HFETR multi-cycle neutronic simulation methodology.