Benchmarking of DeCART2D against critical experiments

The benchmark calculation against various critical experiments has been performed to validate the 2-dimensional whole core transport code DeCART2D and its multi-group cross section library. In addition, several multi-group libraries provided by our own library processing system are employed to investigate the dependency on both the version of the nuclear data library and the number of neutron energy groups. Although these experiments are 3-dimensional, DeCART2D is able to simulate these experiments directly with a consideration of the axial leakage, which can be defined as the multiplication of the diffusion coefficient with the measured geometrical buckling. The calculated solutions for a critical condition are compared with the measured data, which include the pin-by-pin fission rate distribution in the central assembly as well as the eigenvalue. The comparison results show that a discrepancy in the eigenvalue is highly different from the multi-group library, whereas there is little difference in the fission rate. In conclusion, it can be seen that the ENDF/B-VII.1 based multi-group library gives the most reasonable solutions.