LUNA INNOVATIONS INCORPORATED — Department of Energy SBIR Phase I: Current commercial reactor fuel performance monitoring uses external power range monitors,

Description

Current commercial reactor fuel performance monitoring uses external power range monitors, and evaluates coolant water for contamination that would indicate failure of a fuel element. Estimates of the localized fission rates and temperature distributions within the reactor core are approximated using nuclear simulation codes. Real-time characterization of local in-core radiation field parameters would let the operation of various reactor designs (whether present PWRs, new modular LWRs, or future Gen-IV high temperature gas cooled reactors) be safely adjusted for optimum generation efficiency and fuel utilization. Luna will develop miniature fiber-optic probe technology to simultaneously measure the following 4 radiation field parameters in real-time from the same location: total neutron flux, thermal neutron flux, gamma flux, and temperature. Reactor and laboratory testing will demonstrate the utility, stability, accuracy, and endurance to radiation at high-temperatures, as well as the ability to read these sensors despite significant radiation fiber darkening. During Phase I, Luna will invent these new sensors. Tests at The Ohio State University Research Reactor (OSURR) will demonstrate their multi- parameter sensing capabilities. During Phase II, Luna will advance and demonstrate the performance of multi-parameter probes, leveraging the high temperature lead-out irradiation facility for fiber optic sensors at the Massachusetts Institute of Technology Reactor (MIT-R) producing a total neutron fluence of 2E20 n/cm2 each 6 week cycle to emulate normal operation or accident conditions. During all irradiations, sensor response will be monitored continuously using Lunas most advanced interrogation platform. Luna will design these probes to support advanced fuel cycle tests in the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL). Lunas fiber optic multi-flux sensors are a cross-cutting technology, designed to support a variety of nuclear power plants (and adaptable to fossil fuel plants with modification) so they can operate safely just below their maximum rated power levels and temperatures to achieve their optimum electrical generation efficiency. By monitoring local neutron and gamma flux and temperature profiles along fuel elements, these sensors can help operators adjust local fission rates for ideal fuel utilization efficiency and can help validate the performance of new fuel designs during in-pile irradiation tests.