M&C 2017
The C5G7-TD benchmark problems are solved by the nTRACER direct whole calculation code employing faithful models of the core configuration and transient control parameters. In the cases of TD1-1 through TD1-3, nTRACER results are compared with those of the SUHAM-TD code of the benchmark originator to confirm the soundness of the solutions. For selected 2-D cases, the nTRACER results are compared with the McCARD Monte Carlo transient simulation results. For the 3-D TD4 problems involving control rod insertions and withdrawals, a fine axial plane model is used first to generate the reference solutions without significant control rod cusping effect. Then coarser axial plane models are used in which the modified approximate flux weighting method is employed as a decusping approach. The results consisting of transient power behaviors and dynamic reactivity changes are presented.
