Development and Validation of Non-Inertial Coordinate System Motion Model Based on System-level 3D Thermal Hydraulic Code

To realize the simulation for three-dimensional thermal hydraulic characteristics of offshore nuclear power plants and provide technical support for operation training, accident diagnosis and safety analysis, this study, based on the PANTHER code, has developed the 1D/3D additional force model, the 3D motion coordinate calculation model, the 3D non-inertial coordinate system motion calculation model and the IO integrated interaction module, which are integrated into the RINSIM simulation platform. Real-time interaction of parameters and on-line switching of motion conditions are realized, and the comparative test verification is completed based on the two-loop single-phase natural circulation test device. The verification results show that the calculation results of each motion condition meet the physical laws, and the calculation error with the experimental value is below 5%, which proves the reliability of the code calculation results under the condition of marine motion. Therefore, the 3D thermal-hydraulic system analysis code developed in this study can be used to simulate the 3D thermal-hydraulic characteristics of offshore nuclear power plants.