FLUID-STRUCTURE COUPLING ANALYSIS OF U-TYPE TUBE BUNDLE IN PWR STEAM GENERATOR

The structural integrity and safety of a steam generator are susceptible to flow-induced vibration. However, due to the intricate internal structure and thermal dynamics of the pressurized water reactor steam generator. Investigating the flow field characteristics and flow-induced vibration of the U-type tube bundle in steam generator holds pragmatic significance. The investigation delves into the flow field characteristics on both the primary and secondary sides of the U-type tubes, as well as the flow-induced vibration response, employing a multiphase flow model and a multiphysics coupling method. The distribution patterns of fluid pressure, temperature, and vapor fraction within the secondary side of both primary and secondary flow fields were investigated. Additionally, the distribution patterns of thermal stress and deformation under steady flow conditions in U-type tubes were determined. The results indicated that the support plates in the 8th and 9th layers have a significant impact on the thermal stress and deformation of U-type tubes. The temperature field and resultant thermal stress induced by fluid heat transfer on both sides of the U-type tube emerge as crucial factors affecting tube deformation.