Comprehensive Monitoring of Reactor Operations with Fiber Optics

While specialized fiber optic point sensors have long been considered for localized temperature and strain monitoring in nuclear reactor cores, reactor-wide operations can potentially be assessed using standard fiber optical cable repurposed as a large distributed array of strain sensors. We report the application of distributed acoustic sensing (DAS) technology on the fiber optic infrastructure at the High Flux Isotope Reactor (HFIR) at the Oak Ridge National Laboratory to sense seismo-acoustic emanations inside the facility. Our results demonstrate the utility of DAS as a supportive monitoring solution for intermittent crane and transportation activities.