Development and Verification of Typical PWR Core Physical and Thermal-hydraulic Steady Coupling Code

In order to more accurately simulate the strong neutronics physical and thermal-hydraulic coupling phenomenon in a typical PWR, ARMcc, a software for the physical and thermal-hydraulic coupling calculation of PWR core, was developed. In the ARMcc program, the physical calculation module is based on the fourth-order nodal expansion method (NEM) and Nodal Green’s function method (NGFM), the thermal-hydraulic calculation module is based on one-dimensional single-phase single-channel heat transfer model and one-dimensional cylinder heat conduction calculation model. The finite volume method and finite difference method were used to solve heat conduction model in ARMcc program. Based on the typical PWR benchmark NEACRP-L-335, the ability of steady-state coupling calculation of the program was verified. The key parameters of the program, such as critical boron concentration and core Doppler temperature, are in good agreement with reference results. The relative deviation between the critical boron concentration and the reference results is less than 0.5%. In addition, the influences of the finite volume method and the finite difference method on the results of the coupling program were studied. The PARCS program was selected as the comparison program. It is found that NGFM+DIF mode can more accurately simulate the core fuel Doppler temperature and core power distribution, NGFM+VOL mode can more accurately simulate the critical boron concentration, and NEM+VOL mode can more accurately simulate the core fuel maximum temperature.