Analysis of the Main Influencing Factors of Marine Environment on the Nuclear Pressure Vessel of Floating Nuclear Power Plants

Nuclear energy inherently possesses both immense utility and significant risks. To ensure global safety, designers of floating nuclear power plants (FNPPs) must thoroughly consider the influence of the marine environment on the reactor pressure vessel (RPV). Wave loads act on the hull of an FNPP, causing structural deformation, which is subsequently transferred to the RPV. Additionally, wave-induced forces generate six degrees of freedom (6-DOF) motion in the hull, resulting in inertial loads. Consequently, the RPV is subjected to both deformation loads transmitted from the hull and inertial loads associated with the 6-DOF motion. To accurately account for the effects of the marine environment while minimizing the computational cost of RPV fatigue analysis, it is essential to identify the primary influencing factors. This study determined that the predominant factors affecting RPV fatigue in an FNPP were the hull’s pitch, roll, and yaw motions. In mechanical analyses of the RPV, including ultimate strength and fatigue assessments, only rotational inertial loads need to be considered, while the influence of translational inertial loads and hull deformation can be neglected.