Raman distributed sensor system for temperature monitoring and leak detection in sodium circuits of FBR

Leak detection in coolant loops of nuclear reactors is critical for the safety and performance of the reactors. The feasibility of using Raman distributed temperature sensor (RDTS) has been studied on a 30m test loop. Temperature in sodium circuits of fast Breeder Reactor (FBR) exceeds 550°C, gold coated fiber is chosen as sensor fibers. Leak is simulated through an artificial micro fissure integrated in the test loop with provision for controlled leak rate. The results are discussed in the paper.