Preliminary Development of System Analysis Code for Traveling-Wave Reactor

Traveling wave reactors (TWR) are high-burnup nuclear reactors designed to operate indefinitely using fertile material such as natural or depleted uranium (DU), light-water reactor (LWR) waste, or thorium as reload fuel. After an initial partial loading of fissile fuel, the TWR will operate for decades without needing reprocessing or further enrichment, until the lifetime of major structural components is reached. For the safety analysis of this kind of reactor, it is necessary to develop a system analysis code. In the present paper, a system code (named as “TRAVELER”) was developed for a conceptually designed traveling wave reactor. In this code, some important models were established in detail, such as core neutron kinetics model, key equipment models (including centrifugal pump, check valve, lower plenum, upper plenum, fuel assembly, to utilize fuel efficiently without uranium enrichment or reprocessing, instead directly using depleted uranium, natural uranium, thorium, spent fuel removed from light water reactors, or some combination of these materials. The name refers to the fact that fission does not occur throughout the entire TWR core, but remains confined to a boundary zone that slowly advances through the core over time. TWRs could theoretically run, bypass flow channel, pipes connecting these major components) and calculation logic under steady state and transient operation condition. The travelling wave reactor system analysis code currently for the thermal-hydraulic analysis of primary heat transport system was finished. It is expected that the present code could be used for the design and safety analysis of travelling wave reactor to be developed in China.