Criticality and rod worth analysis of the DNRR research reactor using the SRAC and MCNP5 codes

This paper presents the analysis of criticality and control rod worth of the Dalat Nuclear Research Reactor (DNRR) using the SRAC and MCNP5 codes. Criticality calculations were conducted for 49 core configurations of the DNRR established experimentally during the startup period. Reactivity worth of the automatic regulating rod was analyzed in comparison with the measurement data. The impact of various nuclear data libraries (ENDF/B and JENDL) on the criticality and control rod worth analysis of the DNRR were also investigated in comparison between the results obtained using the two codes and the measurement data. The results show that the criticality was predicted within 770 pcm for the calculated cases using the two codes with the ENDF/B-VII.0, JENDL-3.3 and JENDL-4.0 libraries. For the working core with 88 fuel bundles, the criticality was predicted with the discrepancy less than 330 pcm compared to the experiments. This implies that the ENDF/B and JENDL libraries are suitable to analyse the criticality of the DNRR core loaded with the Russian VVR-M2 fuel type. Reactivity worth analysis of the AR rod shows the results were in agreement among the three nuclear data libraries with the discrepancy less than 5%. In most cases, the relative discrepancy is less than about 12% compared to the measurements. The largest discrepancy of the integral reactivity worth is about 17%.