Effect of Different Temperature and Nuclear Data Libraries in Criticality Calculations of 300 MWt Molten Salt Reactor

Abstract

The Molten Salt Reactor (MSR) is a type of reactor in which coolant and fuel are blended with liquid salts. Liquid fuel enhances heat transfer and temperature control, establishing the MSR as one of the Generation IV reactor types. This study aims to analyze the impact of temperature variations on MSR reactor criticality and evaluate the effect of different nuclear data libraries, namely JENDL 3.2, JENDL 3.3, and JENDL 4.0, in neutron analysis. The observed temperature variations are 600 K, 700 K, 833 K, 903 K, and 1000 K. The analysis spans low to operational temperatures to comprehend reactor performance under differing thermal conditions. The study is conducted on a 300 MWTh MSR design, utilizing SRAC2006 with PIJ and CITATION modules for calculations. The results reveal the impact of temperature variations and nuclear data library disparities on reactor criticality. The outcomes demonstrate that higher temperatures correspond to lower values of the effective multiplication factor. At lower temperatures, neutrons experience greater moderation compared to higher temperatures. As a result, a higher number of thermal neutrons influences an increased probability of fission reactions within the reactor. Different nuclear data libraries also yield varied criticality values due to differing cross-sectional areas and quantities of data within each JENDL library. JENDL 4.0 generates the highest criticality value, attributed to elevated cross-sectional regions of each respective nuclear data entry and a greater quantity of nuclear data entries than JENDL 3.2 and JENDL 3.3.