Development of open code system for core design of boiling water reactor

A new core design system for the Boiling Water Reactor (BWR), HANCS, has been developed. HANCS consists of HIDEC, ALLIS and NORMA, which are open source codes. HIDEC which consists of MVP2.0 and ORIGEN2.1 performs the assembly calculation. ALLIS generates the nuclear constants library for the core calculation. NORMA is introduce in order to perform the core calculation. HANCS was developed by coupling these codes with some other utility programs. HANCS was verified by comparing the calculation results by CASMO-SIMULATE as the reference code. In the verification, the results of the core calculation, such as k-effective, the relative power, the void fraction and the fuel temperature, were compared for the initial loading core and the equilibrium core. In the initial loading core analysis, the calculation results of HANCS agreed well with those of CASMO-SIMULATE under both the zero power condition and the full power operation. In the equilibrium core analysis, although the difference of the void fractions between HANCS and CASMO-SIMULATE was found, the void fractions finally agreed well with those of CASMO-SIMULATE by changing the thermal-hydraulic options of HANCS. The other results also agreed well. It is concluded by the verification that HANCS is appropriate for the BWR core analysis. (author)