Study on calculation difference of the SCWR core steady state analysis code

A coupled neutronics/thermal-hydraulics (N/T) three dimensional code system SNTA is developed for SCWR core steady state analysis.This paper studies the calculation difference between the SNTA code and the SRAC code. By using the impacts exclusive method, it is confirmed that the calculation difference between these two code is caused by the different feedback of the reaction cross-section. The reaction cross-section data and the energy group structure of the SRAC code differs from the SNTA code, and the density coefficient of reactivity calculated by the SRAC code is higher, which means the feedback of the density and power distribution is bigger and the axial power distribution varies rapidly.Compare to the SRAC code, the SNTA is more suitable for the SCWR core steady state analysis by coupling neutronics and thermal-hydraulics. (authors)