Industrial Chemistry
Open Access

Abstract

A set of KRITZ-2 experiments light water moderated lattices with uranium oxide and mixed-oxide fuel rods, at room and elevated temperatures, performed in the early 1970â�?�?s have been assessed. Using the MCNP6.1 code with the most recent cross section libraries: JENDL-4 and ENDF/B-VII.1, the critical experiments KRITZ: 2-1, KRITZ: 2-13, and KRITZ: 2-19 were analyzed. We have used the Makxsf and NJOY utilities to handle the data in the specific temperatures not available in the MCNP6.1.1 original data. The detailed comparisons of the calculated and measured effective multiplication factors and pin power distributions for UO2 and MOX fuelled cores presented in this work demonstrate a good agreement between calculation and measurements. The maximum deviation of the calculation from the experimental data for keff, is 0.58% (absolute value) obtained for the KRITZ 2:1at 248.5�?°C using ENDF/B-VII.1 data. To investigate better the influence of cross sections differences on the reactivity and temperature coefficient, we break down the infinite multiplication factor into its components using a pin cell model. We have also calculated the non-leakage probability and the associated temperature coefficient. For the Reactivity Temperature Coefficient, our analysis has shown that the tendency of a negative error (overestimation by calculation of the absolute value of the RTC) usually observed when analyzing similar UO2 and MOX LWR lattices is confirmed. However, the level of the calculation error has been reduced significantly by using Monte Carlo modeling associated with the most recent nuclear data libraries.

Biography

Email: selouahdani@gmail.com