Coupling of the neutron diffusion code SKETCH-N and the thermal-hydraulics system code ATHLET for VVER-1000 calculations
28th Symposium of AER on VVER Reactor Physics and Reactor Safety (2018, Olomouc, Czechia)
Reactor physics experiments and code validation (benchmarks)
This article presents a newly developed coupling between the ATHLET and SKETCH-N computer codes. Firstly the SKETCH-N neutron diffusion code and the ATHLET thermal-hydraulic system code are described. After that the coupling scheme and the coupling program is introduced. The coupling was tested on a VVER-1000 fuel pin cell model. This calculation showed that the coupling is functional. Then the coupling program was applied to calculate the steady-state condition described in the Kalinin-3 VVER-1000 benchmark. The SKETCH-N – ATHLET results were compared to experimental data provided in the benchmark description and to results calculated by SKETCH-N – SKAZKA. SKAZKA is a core thermal-hydraulic module which is coupled with SKETCH-N and was previously verified for VVER-1000 core calculations. The newly calculated results show good agreement with the experimental data and their accuracy is at least as good as the accuracy of the SKETCH-N – SKAZKA calculations. The comparison was made for 2D assembly-wise power density distribution and for 3D power density distribution in the fuel assemblies.