Analysis of MSR Benchmark by Using the Code DYN1D-MSR

A one-dimensional code DYN1D-MSR for transient analysis of Molten Salt Reactors – MSR was developed in FZR. The code is based on the well know three-dimensional code DYN3D. The neutron kinetics routines for axial direction calculation from DYN3D are combined with new models of delayed neutrons production and thermal-hydraulic. The results from the Molten salt Reactor Experiment were used to validate the code. After the successful validation several transients typical for the liquid fuel system were analyzed using the design data of the Molten Salt Breeder Reactor. The results of all transients (overcooling of fuel at core inlet, reactivity insertion, and fuel pump coast-down) have shown that the dynamic behavior of MSR is stable when the coefficients of thermal feedback are negative.