To further improve the stability and accuracy of software calculation,and to confirm,evaluate and improve the important model in the software COSINE,the system safety analysis code cosFlow in the COSINE thermal-hydraulic software package was used to model and calculate the thermal-hydraulic physical process during the core reflooding stage of large-break loss-of-coolant accident(LOCA)in a nuclear power plant.The calculation modeling was based on the Rod Bundle Heat Transfer(RBHT)experiment,and the results of the experiment were used to examine the system safety analysis code.The calculation results show that the change trend of the wall temperature of the rod bundle is basically consistent with the experimental data,indicating that cosFlow can accurately analyze the progress of quench front in the large-break LOCA.However,the progress speed of the quench front is faster in the early stage and slower in the later stage compared to the experimental results of RBHT.It is speculated that this discrepancy may be attributed to the significant axial temperature gradient in the heating rod as well as a lack of axial heat conduction module in the original code.Therefore,the future code development and research will focus on improving the thermal-hydraulic transfer model of the progress of quench front.
COSINE packageRefloodingQuench frontWall temperature
维普
万方数据
