(363d) Fractional Neutron Point Kinetic Modeling of the UMass Lowell Research Reactor

Fractional derivative order modeling has been the subject of much study for many physical processes in recent years. One such process is the diffusion of neutrons in a nuclear reactor, which can be described as a sub-diffusive process when the underlying qualifiers of the diffusion assumption are challenged. This has led to the development of a fractional neutron point kinetics (FNPK) model for a nuclear reactor. This work provides an analysis of the neutron density response of the isothermal FNPK model, as
well as the FNPK for the UMass Lowell research reactor (UMLRR). Several scenarios of the neutron source term as well as varying reactivity insertion are tested on the isothermal model, and analysis on the effects of the fractional parameters κ and τ^κ on predicted neutron density is presented. A detrended fluctuation analysis is performed on UMLRR experiment data, producing the applicable κ values for modeling of the reactor. Finally, a designated UMLRR experiment is simulated using the FNPK coupled with two-temperature, two-poison feedback for several τ^κ values to determine the applicability of the FNPK model.